tag:blogger.com,1999:blog-53594556089983314742024-03-27T14:38:06.784+08:00Just Another Japanese Mahjong BlogThe articles posted here are translations of articles by me.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.comBlogger35125tag:blogger.com,1999:blog-5359455608998331474.post-28860857603246626362012-03-21T06:14:00.002+08:002012-03-21T06:16:21.553+08:00Riichi theory(7): Decision between tenpai with points difference - Part 3Source: <a href="http://blog.jpmahjong.net/read.php/621.htm">http://blog.jpmahjong.net/read.php/621.htm</a><br />
<br />
Lastly, we'll have an example to end this.<br />
<br />
[The image with the K-ON background.]<br />
<br />
In this situation, we're the dealer and the round is Ton 4 of a hanchan. We reached tenpai very early, and there are many choices to deal with this.<br />
You can discard 2,3 pin and be in damaten/riichi or discard chun and declare riichi, but there is only one answer.<br />
<br />
Damaten on the dora 3 pin might not be an easy wait either.<br />
<br />
In addition, you should give up how the intermediate games' players think, like discarding 3 pin and declaring riichi to lure out 2 pin.<br />
There are only two 2 pin left, the chances of winning is slim. Added to the fact that it is next to the dora, there is no one who would fall for such tricks in Houou level games.<br />
<span style="color: red;">You should only set traps when the chances of tsumo is low.</span><br />
<br />
Discarding 2 pin and declaring riichi and tanki on the dora to bet on a tsumo is an extreme method. Tsumo gives you haneman and ura-dora gives you baiman.<br />
If this is all last and you're behind by alot, you can play this way.<br />
But in this situation, a tsumo mangan is more than enough.<br />
<br />
<span style="color: red;">Discarding chun here and declaring riichi should only be limited to this hand.</span> <br />
It's early and the chances of tsumo 1/4 pin is high.<br />
And there's also a chance of having ura-dora 1 and reaching haneman.<br />
(But in the actual situation, the other players all went into betaori after the riichi. orz)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com7tag:blogger.com,1999:blog-5359455608998331474.post-78546051026895095892012-03-18T22:50:00.002+08:002012-03-18T22:54:14.557+08:00Riichi theory(7): Decision between tenpai with points difference - Part 2There's only one part left after this... <br />
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Source: <a href="http://blog.jpmahjong.net/read.php/621.htm">http://blog.jpmahjong.net/read.php/621.htm</a><br />
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<u><b>Hands with a difference of 2 han</b></u><br />
<br />
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<br />
Discarding 7 sou here will not give you pinfu and there's a 2 han difference between the good shape and the bad shape.<br />
<br />
In this kind of situation, the key here is the amount of dora that you have.<br />
<br />
<span style="color: magenta;">You have no dora</span><br />
The riichi with the good shape is only worth 1300 points, whereas the riichi with the bad shape is four times of that, therefore it is better. Without any dora, declaring riichi with the bad shape is the basics.<br />
<br />
<span style="color: magenta;">You have one dora(or there are other yaku worth 1 han, like tanyao)</span><br />
A damaten with a bad shape(5200), riichi with a good shape(2600) and riichi with a bad shape(8000) are all possible choices. To make a decision, you'll have to look at the points situation here.<br />
In a situation where the points are even, most people will declare riichi with a good shape. Even though damaten is worth twice that of riichi, but if you factor in ura-dora and various other advantages, I feel that riichi is a better choice, especially when you're waiting for number tiles like 3 and 7.<br />
If you're after security, or if you're in the lead, you can choose to stay in damaten. This will give you the possibility of going into betaori.<br />
If it's close to the end of the game and you need tsumo haneman for gyakuten, declaring riichi with a bad shape can be a possible solution.<br />
<br />
<div style="color: magenta;">
<span style="color: magenta;">You have</span> two dora</div>
Normally, the condition should be the same as that of dora 1. In a situation where the points are even, declaring riichi with a good shape is superior to declaring riichi with a bad shape.<br />
<br />
<span style="color: magenta;">You have</span><span style="color: magenta;"> three dora</span><br />
If riichi and damaten are both worth mangan, declaring riichi with a good shape is obviously better.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com5tag:blogger.com,1999:blog-5359455608998331474.post-57429932305066327762012-03-18T02:07:00.003+08:002012-03-18T22:26:25.585+08:00Riichi theory(7): Decision between tenpai with points difference - Part 1I'll be separating the article into parts because it's really long. :( <br />
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Source: <a href="http://blog.jpmahjong.net/read.php/621.htm">http://blog.jpmahjong.net/read.php/621.htm</a><br />
<br />
We're basically at the end of the riichi theories, which is also the hardest part to understand.<br />
<br />
Everyone should have had hands that can go into tenpai with different waits, and hands with a good shape that has a lower value than hands with a bad shape. For example:<br />
<br />
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<a href="http://2.bp.blogspot.com/-FaV7kW7rRWs/T2LAMl6Ia-I/AAAAAAAAAJs/5qHwj3GbP4M/s1600/image49.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="43" src="http://2.bp.blogspot.com/-FaV7kW7rRWs/T2LAMl6Ia-I/AAAAAAAAAJs/5qHwj3GbP4M/s320/image49.jpg" width="320" /></a></div>
<br />
This hand has three choices.<br />
1. Good shape(Discard 7 sou) riichi<br />
2. Bad shape(Discard 4 sou) damaten<br />
3. Bad shape(Discard 4 sou) riichi<br />
<br />
As mentioned before, you should declare riichi when you have a good shape, therefore there's no need to consider the first option.<br />
The point of this article is to find out which is the correct method.<br />
<br />
I'll first introduce an important theory.<br />
<span style="color: red;">The winning rate of riichi with a good shape is similar to that of damaten with a bad shape.</span><br />
<br />
This theory is based on the huge amount of statistics by 凸本. If riichi and damaten has the same amount of points, it is more advantageous to declare riichi. This is due to ippatsu and ura-dora.<br />
<br />
Hence<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-QvgVSqW0_FI/T2TPWb85FfI/AAAAAAAAAJ4/ff_JP9_Vo5o/s1600/image50.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="43" src="http://2.bp.blogspot.com/-QvgVSqW0_FI/T2TPWb85FfI/AAAAAAAAAJ4/ff_JP9_Vo5o/s320/image50.jpg" width="320" /></a></div>
<br />
For this type of hand, discarding 1 wan and declaring riichi is better than discarding 4 wan and staying in damaten. <br />
<br />
As for the example in the beginning, riichi with a good shape is 3900 points, while damaten with a bad shape is 5200 points. Similarly, riichi with a good shape is definitely better than damaten with a bad shape. A 3900 points ryanmen riichi has a winning average of 6000 points and above.<br />
<br />
Then how does a good shape and a bad shape compare when declaring riichi?<br />
For this kind of points, the good shape is more advantageous. The riichi with the bad shape is 4 han 30 fu, the effectiveness of ura-dora etc will be reduced. However, the winning rate will be a grade lower and the expected value is not comparable to that of the riichi with the good shape.<br />
Hence, unless it's all last where you need tsumo haneman or other special situations, declaring riichi with a good shape is the correct answer. This sort of shape is worthwhile for everyone to take note.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com2tag:blogger.com,1999:blog-5359455608998331474.post-5527424936148779742012-03-09T21:18:00.002+08:002014-02-03T10:15:20.564+08:00Riichi theory(6): Tips to riichiSource: <a href="http://blog.jpmahjong.net/read.php/620.htm">http://blog.jpmahjong.net/read.php/620.htm</a><br />
<br />
The previous articles introduced a few commonly seen examples of whether or not to declare riichi. Next, we'll discuss what tile you should declare riichi with.<br />
<br />
It may seem like a trivial matter, but as the error piles up, it may adversely affect your results.<br />
<br />
<u><b>Choose the tenpai that lets you win easily</b></u><br />
This can be considered a basic tenet of riichi, for example:<br />
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<a href="http://2.bp.blogspot.com/-mW7HM8427xs/T1nb8nxKcoI/AAAAAAAAAJE/xFoui0_HA8s/s1600/image44.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-mW7HM8427xs/T1nb8nxKcoI/AAAAAAAAAJE/xFoui0_HA8s/s320/image44.jpg" height="42" width="320" /></a></div>
<br />
I believe that everyone would discard 4 sou and riichi.<br />
<br />
Sometimes, a tile isn't necessarily easier to win on just because it's been discarded less. In the above example, even if a nan has been discarded and not a single 4 sou has been discarded, declaring riichi and waiting on nan is still the correct choice. <span style="color: red;">A guest wind tile that has been discarded once is a very good wait</span>.<br />
<br />
What about this hand?<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-1YnL72UxNts/T1nzijG7FbI/AAAAAAAAAJM/nD8XCsNk6ok/s1600/image45.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-1YnL72UxNts/T1nzijG7FbI/AAAAAAAAAJM/nD8XCsNk6ok/s320/image45.jpg" height="37" width="320" /></a></div>
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It's a no brainer to declare riichi here with dora 3. However, I'll only give you 90 marks if you declare 9 pin here. Personally, I would discard 2 wan here and wait on tanki 1 wan. Even though the number of tiles you can wait on is one lesser, there are two advantages in waiting for 1 wan.<br />
1. 1 wan is more difficult to use compared to 3 wan, and it is much easier for it to be discarded. This effect is much more pronounced when the riichi is an early one and there are no safe tiles.<br />
2. After discarding 2 wan, everyone will discard it as it's a genbutsu. 2 wan will gradually become kabe, thereby increasing the chances of someone discarding 1 wan.<br />
<br />
The winning rate of 1 wan here should be higher than that of 3 wan.<br />
<br />
<u><b>Prioritize</b></u><u><b> ankou of </b></u><u><b>terminal tiles</b></u><br />
Hands that do not have pinfu, should retain ankou of terminal tiles if possible. Like the following:<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://1.bp.blogspot.com/-m8GlSBEtxRQ/T1n3aJO58YI/AAAAAAAAAJU/XQqXiGf97pI/s1600/image46.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://1.bp.blogspot.com/-m8GlSBEtxRQ/T1n3aJO58YI/AAAAAAAAAJU/XQqXiGf97pI/s320/image46.jpg" height="50" width="320" /></a></div>
<br />
You should never discard 2 pin, but discard 3 pin here.<br />
Terminal ankous are worth 8 fu, and the fu of the hand will be 40 fu if you get a tsumo. There's a difference between 1000 - 2000 points and 1300 - 2600 points.<br />
<u><b><br /></b></u>
<u><b>Chance of ura-dora</b></u><br />
Ura-dora is an important right of riichi, but a careless discard can affect your chances of getting ura-dora.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-4pZLr-IbHb4/T1n-tuPZF3I/AAAAAAAAAJc/P-OzSUfnZn4/s1600/image47.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-4pZLr-IbHb4/T1n-tuPZF3I/AAAAAAAAAJc/P-OzSUfnZn4/s320/image47.jpg" height="42" width="320" /></a></div>
<br />
In normal situations, you would discard 5 wan and not 2 wan, and declare riichi. The hand is obviously aiming for ura-dora in order to reach mangan, and therefore should increase the chances of getting ura-dora.<br />
<br />
However, there are exceptions to this.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-pS9yEy-QRnQ/T1oAx7U9rTI/AAAAAAAAAJk/62uFJEtryd4/s1600/image48.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-pS9yEy-QRnQ/T1oAx7U9rTI/AAAAAAAAAJk/62uFJEtryd4/s320/image48.jpg" height="52" width="320" /></a></div>
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The current round is all last and you're the dealer, the difference between you and the top player is 20000 points. Winning with a riichi tsumo mangan and getting a renchan in order to achieve gyakuten is a good idea, however, it would be perfect to get a tsumo haneman and achieve gyakuten in one shot.<br />
<br />
Getting an ura-dora 1 would only mean an increase of 300 points, whereas ura-dora 2 gets you a haneman. Hence in order to increase the chances of getting ura-dora 2, it would be better to discard 8 wan here.<br />
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The next article will be about making decisions between han value and number of waits during riichi.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com4tag:blogger.com,1999:blog-5359455608998331474.post-74535034156730782962012-03-07T20:52:00.003+08:002012-03-07T20:57:16.803+08:00Riichi theory(5): Tenpai with yaku having a bad shapeSource: <a href="http://blog.jpmahjong.net/read.php/616.htm">http://blog.jpmahjong.net/read.php/616.htm</a><br />
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This section will explaining the benchmark of tenpai with yaku having a bad shape. There is actually very little difference between this part and other situations with bad shape.<br />
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<u><b>Instant riichi with a 2600, 5200 point hand(including riichi)</b></u><br />
<br />
<div class="separator" style="clear: both; text-align: center;">
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There is no problem with declaring riichi immediately with this hand at all.<br />
<br />
However since you can win in damaten with this hand, there are cases where people stay in damaten. You can choose to stay in damaten, if you realize that the current situation is dangerous or there's a situation that warrants going into betaori for.<br />
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<u><b>Damaten with a 5200 points hand</b></u><br />
The majority of modern mahjong players would stay in damaten with a 5200 points hand that has a bad shape. The only exceptions are when the current round of discard is early or when it's obvious that someone is attacking. (If there's already a situation where three exposed melds are made.)<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://1.bp.blogspot.com/-kucBN1Evfqw/T1aO6JMkgbI/AAAAAAAAAIs/bx2EDYc3L6U/s1600/image41.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="59" src="http://1.bp.blogspot.com/-kucBN1Evfqw/T1aO6JMkgbI/AAAAAAAAAIs/bx2EDYc3L6U/s320/image41.jpg" width="320" /></a></div>
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Riichi only increases the points to 8000, and getting ura-dora would be pointless as the effectiveness is diminished. However if it's still early, there's a good chance of getting tsumo, you can try gunning for a ura-dora 1 haneman.<br />
<br />
<u><b>Tenpai with a [really bad shape]</b></u> <br />
A really bad shape refers to waiting on tiles that no one will discard, like a dora in the middle of a suit. For example:<br />
<br />
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<a href="http://3.bp.blogspot.com/-Efxx_extnoA/T1dQ6QrJ2XI/AAAAAAAAAI0/Ei0yGwf1gEs/s1600/image42.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="39" src="http://3.bp.blogspot.com/-Efxx_extnoA/T1dQ6QrJ2XI/AAAAAAAAAI0/Ei0yGwf1gEs/s320/image42.jpg" width="320" /></a></div>
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Or an even more extreme example:<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://1.bp.blogspot.com/-IT3xl7LiMRY/T1dSAIrG3OI/AAAAAAAAAI8/xzgHTiuPHP8/s1600/image43.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="39" src="http://1.bp.blogspot.com/-IT3xl7LiMRY/T1dSAIrG3OI/AAAAAAAAAI8/xzgHTiuPHP8/s320/image43.jpg" width="320" /></a></div>
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In the first example, waiting for a 5 wan to turn it into a 3 sided wait is a negative way to play. Beginners tend to assume that no one will discard the dora 7 wan. They will continue to wait even if the current situation is impossible to change tiles with. This is an unwise play style. Since you understand that the dora is a tile that will not come out even if you are in damaten, then you should also know that <span style="color: red;">the side effect of riichi that decreases your winning rate is also hugely reduced</span>. It'll at least be a mangan if you declare riichi and tsumo the dora, and it'll be haneman if you get ura-dora 1. Why not just declare riichi?<br />
<br />
The second example follows the same reasoning. No one would simply discard a dora in the middle of a suit. Personally, Iwould declare riichi and aim for a tsumo.<br />
True, this type of hand would usually end in ryuukyoku.(This type of dora tanki tenpai has a winning rate of 20 to 30 percent) However, a haneman is guaranteed if tsumo is achieved, and a baiman is possible if there is an ura-dora. It doesn't matter if the winning rate is a little low, right?<br />
<br />
The next time will be discussing commonly used techniques during riichi.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-56609780127249045902012-03-02T09:30:00.003+08:002012-03-04T22:05:11.875+08:00Riichi theory(4): Tenpai with no yaku having a bad shapeSource: <a href="http://blog.jpmahjong.net/read.php/614.htm">http://blog.jpmahjong.net/read.php/614.htm</a><br />
<br />
Next, we'll be discussing about tenpai with no yaku having a bad shape. (And also hands that shouldn't be in damaten.)<br />
<br />
The biggest difference between bad shapes and good shapes, is that the former will need to consider the amount of effective tiles that can turn it into a good shape. As there is very little chances of winning, if your hand value is low or the current situation is dangerous, you can choose to go into betaori.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://3.bp.blogspot.com/-6DZI9uSJQ_4/T0-_b1d0GyI/AAAAAAAAAHk/Z3wG56r9jWo/s1600/image35.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="42" src="http://3.bp.blogspot.com/-6DZI9uSJQ_4/T0-_b1d0GyI/AAAAAAAAAHk/Z3wG56r9jWo/s320/image35.jpg" width="320" /></a></div>
<br />
Unless the current situation is really dangerous, there's no problem with declaring riichi with this hand.<br />
<br />
Beginners like to wait for 4 man before declaring riichi. <span style="color: red;">Everyone has to remember that the tile you want to draw right now is 2 man, not 4 man, while the chances of drawing 4 man is the same as 2 man.</span> <span style="color: black;">If you draw 5 wan first, and then draw 4 wan later, you'll be in furiten. You can see that it is not effective to wait for a ryanmen here.</span><br />
<br />
There are also those who would only declare riichi if they draw 5 wan, which is also a loss. If you had declared riichi earlier, it would have the same effect as doing it after drawing 5 wan. It's very important to restrict the discards of your opponent. Not only that, while your hand is damaten, your opponent's 2 wan is able to pass and the number of tiles you can win on decreases by one. <br />
<br />
If you tsumo 2 wan, 1300-2600 points should be a pretty good return.<br />
<br />
Then what about this type of hand?<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-kTeabWMgELI/T1AThF4MqnI/AAAAAAAAAHs/tofaC0YMKAM/s1600/image36.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="42" src="http://4.bp.blogspot.com/-kTeabWMgELI/T1AThF4MqnI/AAAAAAAAAHs/tofaC0YMKAM/s320/image36.jpg" width="320" /></a></div>
<br />
There are two tiles that you can draw to turn into ryanmen, but you should just declare riichi. After declaring riichi, you can win from any of the other player's discards. Even though the number of tiles that allow you to change into ryanmen has doubled, you need to draw it yourself to use it. By my standards, I will only wait for tiles to change into a better shape only if there are 4-5 types. If the current discard round is already in the middle rounds, this standard will be stricter.<br />
<br />
<u><b>Number of dora and riichi judgement</b></u><br />
Normally, if your hand has more than 2 dora, <span style="color: blue;">you should just declare riichi regardless of the shape</span>.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-cNuiwMNiyIg/T1AW0P7UHgI/AAAAAAAAAH0/43ZeETJepDI/s1600/image37.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="42" src="http://4.bp.blogspot.com/-cNuiwMNiyIg/T1AW0P7UHgI/AAAAAAAAAH0/43ZeETJepDI/s320/image37.jpg" width="320" /></a></div>
<br />
There are 4 types and 16 tiles that allows you to change to ryanmen when you have shanpon. Not only that, you'll also get pinfu. However when you have dora 2, there's nothing wrong with declaring riichi immediately.<br />
<br />
If there are not many tiles that you can use to change to ryanmen when the dora is only 1, just declaring riichi is also a tesuji in modern mahjong. Getting a mangan with tsumo and 1 ura-dora is not a rare occurrence.<br />
<br />
As for pinfu-nomi that doesn't have any dora, the return is too low, the risk of riichi is relatively larger. You can choose to remain in damaten in this situation, and going to betaori if a dangerous situation arises.<br />
<br />
<u><b>Tanki tenpai</b></u><br />
A tanki tenpai that only lacks a jantou will be waiting for tiles to turn into a good shape in most situations, the reason is that the number of tiles that you can use is a lot.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-6q6s3aETOGg/T1Ac-yWFg-I/AAAAAAAAAH8/_aSuhk6H2Uw/s1600/image38.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="43" src="http://2.bp.blogspot.com/-6q6s3aETOGg/T1Ac-yWFg-I/AAAAAAAAAH8/_aSuhk6H2Uw/s320/image38.jpg" width="320" /></a></div>
<br />
If you have 2-3 dora, you can discard 1 wan and declare riichi. If you have no dora, discard 2/4 pin and go for a tanki wait in damaten. There are many tiles that can be used to change your wait... 2356 wan, 69 sou, 5689 pin can be used to change into a good shape. Not only that, tanki wait on a guest wind is also a good choice.<br />
<br />
<u><b>Deciding whether or not to be in tenpai</b></u><br />
In some situations where you have a tenpai with bad shape, choosing not to be in tenpai and going for a good shape is another common method. The following is an example:<br />
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Discarding 36 wan is tenpai without any yaku. However, discarding 9 pin here is a what an advanced player would do. 3456 wan is a very good shape mentioned earlier with many effective tiles. This hand will be able to turn into a tanyao pinfu. Regardless of winning rate or value, it's far superior to a 1300 points riichi hand.<br />
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It's important to be able to decide whether or not to be in tenpai. Beginners should try to understand it properly.<br />
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The next section will be about tenpai with yaku having a bad shape.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com3tag:blogger.com,1999:blog-5359455608998331474.post-44717023836260220222012-02-23T02:16:00.001+08:002012-02-23T02:22:27.214+08:00More on ryanmen tenpai with yasume and takameSource: <a href="http://blog.jpmahjong.net/read.php/612.htm">http://blog.jpmahjong.net/read.php/612.htm</a><br />
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A reader raised a question about the previous article, regarding yasume and takame.<br />
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For example, if the hand is:<br />
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The yasume of 6 wan is worth 2000 points, while the takame of 9 wan is 7700 points. I mentioned that you should immediately declare riichi with this type of hand, but he feels that damaten is more advantageous. The reasoning is shown in the hand below.<br />
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Similarly, it's hand with takame of 7700 points and yasume of 2000 points. 凸本 mentioned before that you can ignore 6 wan with this sort of hand. Then could you follow suit with the previous menchin hand? If you follow suit, would a damaten be more advantageous?<br />
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If you only win on the takame with this sort of pinfu hand, it becomes a tenpai with a bad shape. According to 凸本's statistics,<span style="color: blue;"> the difference between the winning rate for damaten with a bad shape and riichi with a good shape is minimal</span>. The problem is when you declare riichi, would the chances of winning on the yasume of 6 wan be higher than in damaten?<br />
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If you only calculate the rate of winning, the rate of winning for 6/9 wan is close no matter if it's damaten or riichi. However, riichi will increase the chances of tsumo and if tsumo depends on chance, the chances of 6/9 wan appearing is higher. Hence, riichi will increase the winning rate of 6 wan.<br />
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The value of the yasume after riichi is 3900 points without ura-dora. The chances of getting ura-dora is 30%, and the value is 7700 points with one ura-dora. Hence, the expected value is 5000 points. If it's the takame, it's a haneman with one ura-dora and 8000 points without ura-dora. The expected value is over 9000.<br />
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If you add the two together, the expected value of over 7000 points is similar to that of the damaten of 7700 points. But don't forget that this result has not factor in the following:<br />
1. Riichi increases the chances of tsumo, increasing the expected value. During damaten, the difference in points after tsumo is only 300 points, but after riichi, but the increase will be larger.<br />
2. The risk of drawing the yasume of 6 wan while in damaten.<br />
3. The advantages that riichi bring: ippatsu and the ability to stop other players from reaching tenpai.<br />
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In summary, it's more advantageous to declare riichi. With exposed melds, you can choose to ignore the yasume. <br />
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You should only be in damaten for this sort of hand if there are very little or no more 6 wan left, or when mangan is enough.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-29717807978358432422012-02-18T00:02:00.001+08:002012-03-04T22:04:48.089+08:00Riichi theory(3): Pre-emptive tenpai hand with good shapeSource: <a href="http://blog.jpmahjong.net/read.php/611.htm">http://blog.jpmahjong.net/read.php/611.htm</a><br />
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For the next three articles, I'll be introducing some commonly seen hands that you should declare riichi with and some hands that you should be in damaten for. Today will be concentrating on hands with tenpai waiting on ryanmen or above. <span style="color: blue;">The reader must note that the discussion here is assuming that no other player is attacking. (riichi,</span><span style="color: blue;"> in tenpai with</span><span style="color: blue;"> multiple exposed melds) To decide whether or not to declare riichi while an opponent is attacking, you should use the offence and defence judgement that was previously mentioned as a baseline.</span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;">All ryanmen tenpai should declare riichi, except for some special situations.</span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">This is the tesuji of modern mahjong.</span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">Then what are the "special situations"? </span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">1. Hands with value haneman and above</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">The most commonly seen ones are either menzen chinitsu or honitsu. </span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">Hands with value haneman and above should be in damaten. The reason is that the 1 han from riichi has little effect here, even not having any value. Your winning rate goes down after declaring riichi, therefore there's no benefit here.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">Then, what about mangan tenpai?</span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">With a hand with 7700 points, riichi's effects are smaller than a 1 or 2 han hand. If everyone has the same points, you can be in damaten to quickly take the lead. But if it's still early, the chances of winning is huge. Or if someone declares riichi, instantly declaring riichi to gamble for a haneman is also a viable choice.</span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">2. All last and not needing the extra points to reach first place </span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">This shouldn't need any explanation. (smile)</span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">Basically, these should be all of the special situations.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">Then does it mean that all the other ryanmen tenpai should declare riichi? Theoretically, that's correct. In a game between advanced players, a pre-emptive riichi is very powerful. Beginner advanced players(especially those around Tenhou's higher level tables) do not dare to declare riichi, crippling their firepower. The following shows a few common examples:</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><u><b>Pinfu dora 1</b></u></span></span></span></span><br />
<span style="color: black;">Beginner advanced players like sanshoku too much, and many of them stay in damaten for a hand like this.</span><br />
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<a href="http://2.bp.blogspot.com/-m9LeepsWuX4/Tz5NyemuI-I/AAAAAAAAAGw/OilRA9dinS8/s1600/image29.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="40" src="http://2.bp.blogspot.com/-m9LeepsWuX4/Tz5NyemuI-I/AAAAAAAAAGw/OilRA9dinS8/s320/image29.jpg" width="320" /></a></div>
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">There are people who stay in damaten just to wait for 7 sou. This type of hand is definitely a bad hand.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">It's true that this hand is at least 7700 points if you draw 7 sou, however the problem is that <span style="color: red;">the chances of someone discarding 14 pin or drawing them yourself is much higher than drawing 7 sou</span>. (The former has 8 tiles, while the latter has 4 tiles.) The result is that hands like this often end up with damaten 2000 points or tsumo 700-1300 points. This is a huge waste. A instant riichi might not let you change tiles if you draw 7 sou, but if someone discards 14 pin, then you'll at least get 3900 points. Not only that, there's also a one in three chance of getting ura-dora, thus increasing the points to 7700 points which is equivalent to damaten pinfu sanshoku. </span></span></span></span><span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">Immediately declaring riichi has a chance of getting mangan, which is not lower than drawing 7 sou and then staying in damaten. With the various benefits of riichi, it's more advantageous to just declare riichi.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">What about this kind of hand?</span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">A hand that is at least 2000 points and as high as 7700 points. Many people will stay in damaten but you </span></span></span></span><span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">should instantly declare riichi with </span></span></span></span><span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">this kind of hand.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">After declaring riichi, even if the yasume appears, there's still a good chance of getting ura-dora and turning the hand into a mangan, and even having a chance of becoming haneman if the takame appears. Drawing the yasume while in damaten is the real tragedy here.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">No matter if the takame is on the inside or the outside, you </span></span></span></span><span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">should immediately declare riichi with</span></span></span></span><span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"> this kind of hand.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">Applying the same logic, you should not wait for ittsu with the hand below but declare riichi immediately.</span></span></span></span><br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><span style="color: red;">An instant riichi with pinfu dora 1 is the basic among the basics</span>.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><u><b>Pinfu-nomi/No yaku ryanmen wait</b></u></span></span></span></span><br />
Then what about pinfu nomi or a no yaku ryanmen wait?<br />
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The mainstream theory in the old days prefer damaten. The reason is that it's unreasonable to spend 1000 points to reach 1300/2000 points. However in today's time, this theory is outdated. This two types of hand are immediately declared riichi with.<br />
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Using pinfu nomi as an example, riichi pinfu is only 2000 points on the surface. However, if you include ippatsu ura-dora etc, the average points of pinfu nomi is above 3000 points. Added to the fact that opponents cannot freely make discards, declaring riichi is advisable.<br />
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Also, when we're in ryanmen wait, we'll rarely consider changing tiles.<br />
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<a href="http://3.bp.blogspot.com/-IdfimFBAlDw/Tz52iO5MiEI/AAAAAAAAAHI/kLFUtLMHHks/s1600/image32.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="41" src="http://3.bp.blogspot.com/-IdfimFBAlDw/Tz52iO5MiEI/AAAAAAAAAHI/kLFUtLMHHks/s320/image32.jpg" width="320" /></a></div>
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Even if you can have tanyao by drawing 36 wan, or dora by drawing 7 sou, you should instantly declare riichi with this kind of hand. Half of the time after tenpai, winning happens within 5 rounds of discards. Even if you have 12 effectives tile, you'll still need 7-8 rounds of discards to draw it. Therefore in many instances, you'll find that before you draw your effective tile, you would already be able to win. This directly affects your scoring ability.<br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><u><b>Pinfu dora 2 </b></u></span></span></span></span><br />
I've seen people who advocate damaten with pinfu dora 2 in some forum.<br />
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An instant riichi with pinfu dora 2 is better. It's at least 7700 points with riichi, there's also a better chance of tsumo haneman. There's a huge difference compared to winning 3900 points with damaten.<br />
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The only acceptable example is the dealer nearing ryuukyoku with a 5800 points tenpai. When the number of round of discards left is not much, maximizing your chances of winning to achieve renchan is a logical method, even though the points is not much. However, immediately declaring riichi is not a bad choice either.<br />
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<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><u><b>Is the current round of discard related?</b></u></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">The aforementioned riichi standard should not be affected by the current round of discard. You should just declare riichi with pinfu dora 1, regardless of whether it's the 1st round or the 15th round. It's true that your chances of winning is low when you're close to ryuukyoku. However, do not forget that the success rate of damaten is also limited. Riichi also has the ability to cause other players to go into betaori, earning you the noten bappu. This is also riichi's intangible advantage.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">In summary, you don't need to consider the current round of discard or tiles changing with pre-emptive ryanmen. There's nothing wrong with an instant riichi.</span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;"><br /></span></span></span></span><br />
<span style="color: blue;"><span style="color: black;"><span style="color: red;"><span style="color: black;">The next time will be discussing examples of tenpai with bad shapes.</span></span></span></span>Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com3tag:blogger.com,1999:blog-5359455608998331474.post-47294864450407710082012-02-14T19:47:00.002+08:002012-02-16T19:39:37.663+08:00Riichi theory(2): Side-effects of riichiSource: <a href="http://blog.jpmahjong.net/read.php/610.htm">http://blog.jpmahjong.net/read.php/610.htm</a><br />
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Previously we mentioned the various advantages of riichi. This time will be about the disadvantages and restrictions. <br />
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<u><b>1. Decrease in winning rate</b></u><br />
Yes, it's is a well known fact that the winning rate after declaring riichi is lower than damaten.<br />
The rate of success of riichi over 60% in ordinary games, whereas it's around 45% in phoenix games. While damaten ryanmen waits have a 60-80% chance of winning, as long as not many discards have been made. Riichi's winning rate is around 60% of damaten.<br />
However as the value of riichi hands are two to three times of the original value, in addition to having a high chance of tsumo, the expected value of riichi hands is much higher than damaten.<br />
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<u><b>2. 1000 points expenditure</b></u><br />
In most situations, the 1000 point fee of riichi is no big deal. However if everyone has a small deviation in points, you might want to take it into consideration.<br />
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<u><b>3. After declaring riichi, all tiles must be discarded unless it's the winning tile or a tile that you can make ankan with</b></u><br />
Riichi is a hand exposing declaration. After declaring riichi, you cannot change your tiles in order to change your wait or increase it's value.<br />
Also, even if you draw a dangerous tile, you must discard it.<br />
In superior level games, examples of dealing ins are often after declaring riichi.<br />
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In summary, the reason why riichi is a main attacking method in Japanese mahjong is <span style="color: red;">because it's advantages far outweigh it's disadvantages</span>.<br />
Naturally, the advantages and disadvantages are affected by different hands and points situations. This is the basis of whether or not to declare riichi.<br />
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However, I can first tell everyone two very important points.<br />
<div style="color: blue;">
1. In Japanese mahjong, situations where you need to be in damaten is very rare.</div>
<span style="color: blue;">2. You lose more points by not declaring riichi when you should than declaring riichi when you shouldn't. </span><br />
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Next, the following articles will discuss these three areas:<br />
1. Hands which you should declare riichi and hands which you should be in damaten for<br />
2. Standards of riichi, tesuji etc<br />
3. Summary of riichi judgement<br />
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To be continued.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-51340124937730466212012-02-14T01:40:00.000+08:002012-02-14T17:24:01.513+08:00Riichi theory(1): What is riichi?Source: <a href="http://blog.jpmahjong.net/read.php/606.htm">http://blog.jpmahjong.net/read.php/606.htm</a><br />
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Riichi is one of the four types of yaku in Japanese mahjong and holds an important position. Starting from today, I will be explaining various judgements related to riichi. <br />
(Discussions related to situation judgements is still work in progress, it's just that collecting examples takes time. They will be posted once they're finished.)<br />
(Translater note: The author is talking about another series of articles related to situation judgements. I decided to translate riichi theory first.)<br />
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To understand how to judge riichi, first you need to understand what is riichi. I've mentioned it before previously in <a href="http://blog.jpmahjong.net/read.php/18.htm">articles</a> of a higher difficulty, but this time is for beginners and the theories will be explained in detail. Today will be about the advantages of riichi.<br />
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Advantage:<br />
Beginners tend to misunderstand riichi. <span style="color: blue;">The most common problem with them is underrating the advantage of riichi. </span>Therefore it's important to understand the benefits of riichi.<br />
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<u><b>1) Increase your hand value</b></u><br />
Many people underestimate the attacking power from riichi. People used to say: "Pinfu-nomi's 1 han is only worth 1000 points, while there's only 2000 points after riichi. There's only 2000 points, so you should damaten."<br />
For now, we won't discuss whether pinfu-nomi should declare riichi, but whether or not riichi can increase your original hand's value by 1 time, and pinfu-nomi is not just 1300 points.<br />
I believe everyone has seen these kind of tiles:<br />
Riichi Ippatsu Tsumo Ura-dora 1<br />
Riichi Ura-dora 3<br />
Riichi Ippatsu Tsumo Pinfu Ura-dora 1/2<br />
With riichi, it's not rare to see examples of worthless hands turning into mangan or haneman. Riichi on average will have 1/3 ura-dora, and winning hands with riichi have ippatsu 20% of the time. If you add these up, in fact riichi has a value of 1.5-1.6 han. According to statistics, winning hands with pinfu-nomi riichi has 3000 points and above on average. Riichi has the ability to increase the value of pinfu-nomi by 3 times or more.<br />
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In addition, riichi will increase your tsumo proportion. If your hand is 2600 points, and you win on another player's discard while in damaten, the difference between the player who dealt in and the other two players is 5200 and 2600 points respectively. However if you declare riichi, even if you tsumo and didn't have any ura-dora, the difference between you and the other players is 5000 to 6000 points. There's a huge difference.<br />
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<u><b>2) Restrict your opponent's dicards</b></u><br />
This is something that is often neglected by most beginners and even some intermediate players.<br />
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Once someone declares riichi, unless the others have good tiles, they will not attack recklessly due to Japanese mahjong's payout system. This way, the opponents have lesser chance of winning. On the other hand, once the opponents have lower chances of winning, <span style="color: red;">the amount of chances that you can draw tiles increases</span>, indirectly increasing the value of the winning hand.<br />
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This explains why players declare riichi with a suuankou tenpai, the main motive is to increase the chances of drawing tiles.<br />
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<u><b>3) Makes certain tiles easier to wait on</b></u><br />
This is a tactic that everyone knows.<br />
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Luring the opponent to discard the suji-pai of the riichi tile(especially 19 suji-pai), guest wind, no chance tiles etc, will achieve the desired result. <br />
However I ask everyone not to abuse this tactic, and only use it when it's suitable.<br />
<br />
As for riichi's disadvantages, they will be discussed after my new year vacation.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-72910664886388006562012-02-13T22:09:00.002+08:002012-02-13T22:09:26.704+08:00Defence theory(16): Tricks to defendingSource: <a href="http://blog.jpmahjong.net/read.php/567.htm">http://blog.jpmahjong.net/read.php/567.htm</a><br />
<br />
In the previous articles, we discussed betaori techniques when someone has declared riichi or when defending. <span style="color: blue;">However, to truly defend is not just about defending when someone attacks. </span>As
the discards increases, the chances of the other players reaching
tenpai increases. If you put in a little effort in some details, you can
avoid dealing in.<br />
<br />
A few commonly seen techniques are shown below.<br />
<br />
<u><b>Discard the good tile first\Keep the safe tile</b></u><br />
For example, like the hand below.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-uwbZH1YZuWw/Tzj4GvXNqPI/AAAAAAAAAFg/Ryqwwn2aIY4/s1600/image20.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="40" src="http://2.bp.blogspot.com/-uwbZH1YZuWw/Tzj4GvXNqPI/AAAAAAAAAFg/Ryqwwn2aIY4/s320/image20.jpg" width="320" /></a></div>
<br />
A hand in iishanten, and the 4 sou is an useless tile.<br />
Let's
assume that you next draw a dead tile, nan. If the situation doesn't
look dangerous, you'd normally discard 4 sou first. This is what it
means by discarding the good tile first.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-PymUnCaCeMM/Tzj5PSOE91I/AAAAAAAAAFo/Gt_aFdasSmY/s1600/image21.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="42" src="http://2.bp.blogspot.com/-PymUnCaCeMM/Tzj5PSOE91I/AAAAAAAAAFo/Gt_aFdasSmY/s320/image21.jpg" width="320" /></a></div>
<br />
The
theory behind discarding the good tile first, is that 4 sou has a
higher chance of becoming a dangerous tile than nan in the future. Since
4 sou is useless to us, you should discard it before someone reaches
tenpai, in order to get rid of the risky tile that would be in your hand
when you reach tenpai.<br />
<br />
The tactic about keeping the safe tile should not be abused.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-2pc6szCEq3s/Tzj8aIirCJI/AAAAAAAAAFw/Qz_HHO0musg/s1600/image22.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="38" src="http://4.bp.blogspot.com/-2pc6szCEq3s/Tzj8aIirCJI/AAAAAAAAAFw/Qz_HHO0musg/s320/image22.jpg" width="320" /></a></div>
<br />
If we change 4 sou to 7 sou, the situation is very different. If you draw nan this time, you should definitely discard it.<br />
Previously
when I was still playing in high level games in 東風莊, I would discard 7
sou and keep nan with these type of hands. But in modern day mahjong
theories, this is a conservative method. In the image above, there are
20 tiles that can be added into the hand. But if we were to discard 7
sou for a safe tile, the number of effective tiles would be 16. This a
significant 20% loss when compared to the former.<br />
<br />
<span style="color: red;">The first condition when keeping the safe tile is to not sacrifice tile efficiency.</span> With the hands below, a safe tile would be discarded if drawn.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://3.bp.blogspot.com/-5fCX7eaBwNs/TzkAasIAHoI/AAAAAAAAAF4/KOF_90XeeiE/s1600/image24.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="47" src="http://3.bp.blogspot.com/-5fCX7eaBwNs/TzkAasIAHoI/AAAAAAAAAF4/KOF_90XeeiE/s320/image24.jpg" width="320" /></a></div>
<br />
At the beginning of the hand, 4 sou should not be discarded, it has a chance of becoming a ryanmen.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://4.bp.blogspot.com/-m5pjmcOjBa8/TzkEQXTNtLI/AAAAAAAAAGA/lATo1AWpLWQ/s1600/image25.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="47" src="http://4.bp.blogspot.com/-m5pjmcOjBa8/TzkEQXTNtLI/AAAAAAAAAGA/lATo1AWpLWQ/s320/image25.jpg" width="320" /></a></div>
<br />
As
2356 pin has effective tiles repeating, it cannot be considered as a
good shape. At the beginning of the hand, 7 sou should be kept, but can
be tricky after the middle discard rounds. <br />
<br />
<u><b>Going into betaori early</b></u><br />
Mahjong
is played by four players, and each player has a 25% chance of winning.
Among them are hands that have very little chance of winning, for
example:<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://3.bp.blogspot.com/-11WoT6Gdq0k/TzkS1ZThajI/AAAAAAAAAGI/PZayv0YGRzQ/s1600/image26.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="47" src="http://3.bp.blogspot.com/-11WoT6Gdq0k/TzkS1ZThajI/AAAAAAAAAGI/PZayv0YGRzQ/s320/image26.jpg" width="320" /></a></div>
<br />
This
is a sanshanten hand with many bad shapes, and there is no way to
increase the speed via calling tiles. If your hand remains this way even
after the 5th or 6th, unless you make godly draws, your chances of
winning is close to zero. Since you can't win, you should try to
minimize your losses. Hence going into betaori is the best choice here.<br />
<br />
Discard
tiles that have been discarded by other players(kamicha would be the
best) in the same discard round, and keep the tiles(like word tiles)
that have a high degree of safety. If someone declares riichi later, you
can remain in a safe state and reduce dealing in to the minimum. This
method also protects you from dealing in to the damaten of other
players.<br />
<br />
Normally, <span style="color: blue;">a sanshanten hand in the 6th discard round and a ryanshanten hand in the 12th discard round has zero chance of winning</span>.
With this sort of tiles, you can either call tiles and try to win or go
into betaori. Just like in poker, it's not possible to have a good hand
every single round. Attempting to win when you have a bad hand will
only cause you to incur more losses.<br />
<br />
The two theories originate from the principle below.<br />
<div style="color: red;">
Discard the dangerous tile before someone reaches tenpai.</div>
<span style="color: red;">Discard safe tiles sequentially after someone reaches tenpai .</span><br />
<br />
This is the true essence of reducing the chances of dealing in.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-18511841270412031312012-02-11T14:09:00.003+08:002012-02-13T22:15:38.797+08:00Defence theory(15): Defence theory against two or more players(Continued)Source: <a href="http://blog.jpmahjong.net/read.php/565.htm">http://blog.jpmahjong.net/read.php/565.htm</a><br />
<br />
This article continues the previous discussion about complicated situations.<br />
<br />
At the beginning of a hand in a phoenix hanchan, the point spread is rather special. Toimen only has 1500 points, while I only lag behind shimocha by 2000 points in third place.<br />
<br />
[First image in <a href="http://blog.jpmahjong.net/read.php/565.htm">http://blog.jpmahjong.net/read.php/565.htm</a>]<br />
<br />
Originally, I had hoped to declare riichi with this hand. It's a good thing even if I knock out toimen and end up as second place. However, it was frightening when kamicha called 3 sets of tiles early in the game. Even though I knew that if kamicha had tsumo, I would end as third place, but because my hand was not in tenpai, I had to go into betaori.<br />
<br />
Shimocha seeing this situation, naturally goes into betaori. The one you have to take special note of is toimen who is in fourth place. I followed kamicha's discard and discarded 7 wan, which toimen pon on, indicating that toimen is not in betaori. As I mentioned previously, attacking during situations where betaori is needed, is a sign of being in tenpai. Therefore not only do you have to defend against kamicha, you have to be careful of toimen.<br />
<br />
I discarded the genbutsu of kamicha 7 sou, I draw 9 sou next. What should I discard?<br />
[Second image in <a href="http://blog.jpmahjong.net/read.php/565.htm">http://blog.jpmahjong.net/read.php/565.htm</a>]<br />
<br />
As both players have exposed melds, we can analyze it a little bit.<br />
<br />
Let's talk about kamicha first. Kamicha called three sets of tiles early in the game, and has been discarding what he drew since the sixth discard. Obviously, he's in tenpai and his hand is not only worth 3900 points. (If kamicha's hand only has 3900 points, with this kind of points situation, there's no need to go into betaori.) Honitsu and toitoihou is the most likely here. <span style="color: red;">In other words, kamicha has at least a mangan, even a 18000 points dealer haneman is possible, that's why it's frightening</span>. As the discards of kamicha is too neat, we are unable to find out which suit he's waiting on. However since kamicha discarded quite a lot of pinzu early, the chances of a pinzu honitsu is the lowest. Also, in order to avoid toitoihou, you must avoid discarding any live tiles. <span style="color: red;">Thus, the 8 and 9 sou in your hand is the most dangerous.</span><br />
<br />
As for toimen, the hand is most likely a tanyao. Since dora was discarded, the value of the hand shouldn't be too high. It would be 3900 points even with aka-dora, the danger is low but you shouldn't be careless. Since you're in betaori, you might as well avoid dealing-in, although the main focus is on kamicha.<br />
<br />
After some deliberation, I discarded 8 pin.<br />
<br />
Although 8 pin is a live tile, it's also the suji-pai of toimen, giving it some degree of safety.<br />
Kamicha discarded 7 and 9 pin earlier on, if kamicha had 7889 pin on the early stages, <span style="color: blue;">he wouldn't have discard 7 and 9 pin<span style="color: black;"> in a situation where honitsu is confirmed</span>. Hence, we can conclude that kamicha discarded 7 and 9 pin while dismantling a taatsu</span>. Since kamicha discarded 5 pin, a ryanmen wait on 58 pin is eliminated, thus 8 pin has a huge chance of passing.<br />
<br />
Game Replay (Click on 全局牌譜 in <a href="http://blog.jpmahjong.net/read.php/565.htm">http://blog.jpmahjong.net/read.php/565.htm</a>)<br />
L0000 鳳南喰赤 平均R2070.2<br />
1位 くるる(七段/R2010/+46) 3位 zeroRX(八段/R2137/-24) 4位 麦わらぼうし(七段/R2037/-36) 2位 kickchi(七段/R2097/+14) <br />
<br />
These sort of safe tile judging in betaori is not easy, as it involves a lot of analysis and theory. Also you'll need to pay attention to other players, to make the correct decision. These two articles can be said to be an example to show everyone what to focus on when finding safe tiles. If there are any more good examples in the future, they'll be posted to be shared with everyone.<br />
<br />
The next article will be about some tricks to defending.<br />
(To be continued)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-30398325116627657662012-02-08T22:35:00.002+08:002012-02-08T22:35:53.089+08:00Defence theory(14): Defence theory against two or more playersSource: <a href="http://blog.jpmahjong.net/read.php/561.htm">http://blog.jpmahjong.net/read.php/561.htm</a> <br />
<br />
For the sake of simplicity, the previous theories assumed that only one player was attacking. However that is not the case in real games. Situations where one player declares riichi and another player pursues riichi or goes into kanzen shinko are not rare.<br />
<br />
The author mentioned before that if your order of discarding during betaori is done properly, it will effectively raise the chances of having safe tiles to discard when many players declare riichi. However, there will still be times when you have no safe tiles to discard. It is at times like this, where making good judgement becomes even more important.<br />
<br />
<u><b>General direction</b></u><br />
The aim of defending is to avoid dealing in, but when this doesn't work, avoid dealing in to big hands is the second best practice. <br />
<br />
When facing riichi from two players and above, avoid dealing in as the value of the hand is hard to estimate. But if there are melded sets, we can estimate the value of the hand with the exposed tiles and discards. If we know that the value of the hand is small, we can ignore that player or deliberately deal in to him. <br />
<br />
<u><b>Finding safe tiles</b></u><br />
Firstly, we need to find genbutsu that both players have, but there may not be any most of the time. The following is the usual way to discard:<br />
1. Genbutsu of both players<br />
2. Genbutsu of one player, suji-pai of the other<br />
3. Suji-pai of both players<br />
4. Suji-pai of one player, non suji-pai of the other<br />
5. A middle tile that is a non suji-pai<br />
<br />
However as safe tiles increase quickly(as any discard by either players become genbutsu for both players), <b>therefore the method mentioned previously where you discard toitsu might not be useful here</b>... Instead, appropriate use of tile reading and situation judging will be of great use here. <br />
<br />
[First image in <a href="http://blog.jpmahjong.net/read.php/561.htm">http://blog.jpmahjong.net/read.php/561.htm</a>]<br />
<br />
Two players declared riichi, what is the safest tile in your hand?<br />
<br />
The safest tile is 1 pin. Four 2 pin and two 1 pin have already been discarded, therefore 1 pin can only be a hell wait.<br />
<br />
If there's no safe tile in the next round, personally I will discard 4 sou. Shimocha made an ankan with 3 sou and 5 sou was discarded 3 times, the chances of 4 sou becoming mentsu is the lowest. As for 8 wan and 3 pin, they are very dangerous as the tiles near them have not been discarded. For this round of discards, if the 4 sou passes, you should be able to make it to ryukyoku.<br />
<br />
After discarding 1 pin, you should be able to make it to ryokyoku without making any dangerous discards. Toimen is waiting on 36 wan and shimocha is waiting on 7 wan.<br />
[Second image in <a href="http://blog.jpmahjong.net/read.php/561.htm">http://blog.jpmahjong.net/read.php/561.htm</a>]<br />
<br />
The next article will talk about more complicated examples.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-2247084482488666792012-02-08T06:36:00.004+08:002012-02-08T06:42:33.338+08:00Defence theory(13): Detailed explanation of each type of melded sets(Part 2)Source: <a href="http://blog.jpmahjong.net/read.php/558.htm">http://blog.jpmahjong.net/read.php/558.htm</a><br />
<br />
The melded sets mentioned in the previous article, all belong to "sakidzuke katachi". What it means is that the melded sets are related to yaku. Sometimes, the first and second melded sets of the opponent may not be related to yaku. The aim of calling those tiles is to get rid of the bad shape of the hand. This type of attack is referred to as "atodzuke katachi", for example:<br />
<br />
[First image in <a href="http://blog.jpmahjong.net/read.php/558.htm">http://blog.jpmahjong.net/read.php/558.htm</a>] <br />
<br />
or<br />
<br />
[Second image in <a href="http://blog.jpmahjong.net/read.php/558.htm">http://blog.jpmahjong.net/read.php/558.htm</a>]<br />
<br />
Normally, "atodzuke katachi" melded sets have a higher value than "sakidzuke katachi", but as the possibility of the hand is heavily restricted, it's not hard to find out what tiles are dangerous. This article will discuss how to defend against this type of attack.<br />
<br />
These two are commonly seen atodzuke yaku:<br />
1) Yakuhai<br />
2) Sanshoku, Itsuu, Honitsu<br />
<br />
Among them, yakuhai has the highest probability of appearing. So once melded sets appear, the first thing you should check for are live yakuhai tiles. (capable of making a koutsu.) If you have such tiles, there are two choices you can take:<br />
The first is to discard it immediately, hoping that the opponent is not in tenpai.<br />
The second is to keep it until the end of the hand.<br />
<br />
If the opponent starts to discard the tiles he draw, then the chances of being near tenpai is high. The live yakuhai tiles now are dangerous tiles, and should not be discarded.<br />
If you've made sure that yakuhai is not possible, then the only possibility now is sanshoku and itsuu. Most of the time, you can rely on the discard pond to estimate the tiles related to yaku, and avoid discarding them. As for the value of the hand, you can estimate using the amount of dora you haven't seen. If the dora is related to yaku(for example the dora is yaochuhai and the hand is hon chanta), you need to be more careful.<br />
<br />
Using a simple example<br />
[Third image in <a href="http://blog.jpmahjong.net/read.php/558.htm">http://blog.jpmahjong.net/read.php/558.htm</a>]<br />
<br />
Kamicha calls 2 pin. You can tell that it's not a honitsu by looking at the discards. You can see four 4 sou and 9 pin, therefore the chances of itsuu and sanshoku is gone. The only possibilities left are hon chanta and yakuhai. From the discards, the possibility of the former is rather high.<br />
The yakuhai that has not appeared yet are haku and hatsu, and since 9 wan is the dora, these three tiles are highly dangerous. Secondly, the tiles that can form shuntsu of 123 and 789, like 78 sou, 2378 wan etc are not safe.<br />
<br />
From the standpoint of the top player, these tiles must not be discarded.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-86319783277721962862012-02-07T00:28:00.000+08:002012-02-07T00:32:26.797+08:00Defence theory(12): Detailed explanation of each type of melded sets(Part 1)Source: <a href="http://blog.jpmahjong.net/read.php/552.htm">http://blog.jpmahjong.net/read.php/552.htm</a><br />
<br />
In the previous article, the author mentioned the important signals related to melded sets. This article will introduce in detail each type of melded sets and things to note.<br />
<br />
As melded sets will expose information regarding the hand, if used appropriately, it will greatly help in making the proper judgement. Our aim is to use the melded sets to deduce the following.<br />
1. Value of the hand<br />
2. Area of waiting tiles(Or from another perspective, which tiles are safer.)<br />
<br />
The following will explain in details the commonly seen types of melded sets.<br />
<u><b>1. Calling of middle tiles</b></u><br />
This can be said to be the most commonly seen melded set in Japanese mahjong. Of course, the melded sets of the opponent are all middle tiles. The largest characteristic about calling middle tiles is that it's difficult to form with other yaku. (Among them, tanyao sanshoku has the highest chance of appearing, but even the chances of getting it is not high.) Hence, the amount of dora in the hand is the determining factor of the hand's value. <br />
<br />
So once middle tiles are called, you first need to estimate the whereabouts of the dora. One hand of game has 7 dora(four indicated dora and 3 aka dora). <span style="color: red;">The more dora you can see, the lower the chances that the opponent has a huge amount of dora</span>. Also, if the attacker is really proactive at calling tiles(for example, calling 1 or 2 mentsu very early), then the chances of having a high value hand is higher. Sometimes when we know that there is a high chance that the opponent only have a 1000 or 2000 points hand, we can consider ignoring them.<br />
<br />
Against calling of middle tiles, it's easier when it comes to defending, as any yaochuhai is a safe tile. However as the area of waiting tiles is narrow, over reliance on suji-pai and one chance tiles, especially dora soba, can be dangerous.<br />
<br />
<u><b>2. Somete</b></u><br />
Like calling of middle tiles, this is also a commonly seen melded set. It's easy to judge if it's a honitsu or chinitsu melded set, as you can see it from your opponent's discards.<br />
<br />
Somete has a narrow area of melded set and can be easily recognized, but it's return is usually higher. Somete usually have at least 3900 points, mangan or even haneman are not a rare sight.<br />
<br />
For this reason, somete has defence theory like suji-pai etc. Unless it's a genbutsu or tiles incapable of becoming mentsu, or else it's a dangerous tile.<br />
<br />
<u><b>3. Toitoihou</b></u><br />
Toitoihou attacks are a common sight in beginners' games, but in higher levels of mahjong games, the chances of appearing is lower. When the opponent often pon tiles, and the discards are made up of random middle tiles, then the chances of toitoihou is large.<br />
<br />
The lethality of toitoihou is not low either, it's normally between 2500 to 8000 points. Additional han values are usually from yakuhai 9 out of 10 times. So if you note the yakuhai that have not yet appeared, you can probably estimate the value of the opponent's hand.<br />
<br />
As toitoihou is always waiting on tanki or shanpon, there are no suji-pai. <span style="color: red;">Live tiles, no chance tiles and yakuhai are all ultra dangerous</span>. Tenpai is usually on easier waits, therefore middle tiles that have been discarded twice are relatively safer. And when we go into betaori, sometimes we would discard koutsu middle tiles. <br />
<br />
<u><b>4. Yakuhai</b></u><br />
Yakuhai tiles are express tickets to winning. You'll get yaku as long as you can pon with it, and as it restricts tile shapes the least, it becomes easier to form hands. <br />
<br />
Not only is it easy to combine it with other common yaku(toitoihou, honitsu), a dealer's double ton or yakuhai dora 2/3 are all powerful attacking methods in Japanese mahjong. <br />
<br />
As the hand varies greatly, it's harder to deduce the value and waiting tile of the opponent's hand. Normally, the first thing you should do is to note the amount of dora tiles that have not yet appeared, and whether or not the opponent's discards show any characteristics of other yaku. <br />
<br />
As for defending, once the signs of being in tenpai appears, treat it as a normal riichi as the waiting tile is not restricted. But as there are melded sets, we can obtain more information regarding what tiles are safe or dangerous:<br />
<br />
a) Tiles that have not appeared, are all dangerous tiles. (Translator note: For those of you who can read Chinese, you might notice that I didn't translate this sentence fully. The reason is that it didn't make any sense. The author said that the tile discarded by the attacking player after making the final mentsu is a dangerous tile. Since the attacker cannot ron on a tile he discarded, how can that be a dangerous tile? I will leave it like this until I understand what he really meant.)<br />
b) Tiles discarded by the kamicha of the attacking player but have not been called, are usually safer. The reason is that this proves that that tile is not need by the attacking player. (If it's a menzen, even if others discard a tile you want, you can't call on it.)<br />
<br />
(As the current section is too long, the rest of the article will be moved to the next section.)<br />
(To be continued.)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com3tag:blogger.com,1999:blog-5359455608998331474.post-81442512513426918352012-02-05T18:40:00.000+08:002012-02-05T18:40:03.860+08:00Defence theory(11): Defence against melded sets(1)Source: <a href="http://blog.jpmahjong.net/read.php/550.htm">http://blog.jpmahjong.net/read.php/550.htm</a><br />
<br />
Starting from this hand, I'll begin discussing about defence against melded sets.<br />
<br />
Everyone might be thinking that defence against melded sets are harder to deal with, as you don't know when the other side is in tenpai. However up to a certain degree, mentsu that are melded allows you to find out the situation of your opponent's hand. From there you can formulate better and more accurate offence and defence tactics.<br />
<br />
Mentsu that are melded, at the very least allows you to know the following situations.<br />
<br />
1. You can predict the yaku your opponent wants, estimate the value of the hand and then the area of waiting tiles from there. Sometimes when we know the opponent has a small value hand, we can consider not going into betaori.<br />
<br />
2. You can know the order of mentsu forming and along with discards, you can find out the area of dangerous tiles more accurately.<br />
<br />
Also, even though the player with melded sets cannot declare riichi, but based on the situation of the game, we can usually estimate whether the opposite side is in tenpai, this sort of tile reading is highly accurate. The following are commonly seen methods of finding out if someone is in tenpai.<br />
<br />
<u><b>1) Opponent's amount of melded sets and time</b></u> <br />
Normally, you know whether an opponent is in tenpai from the following:<br />
a. 3 melded sets at any time<br />
b. Several tiles change occurring after 2 melded sets<br />
c. 1 melded set near the end of the hand<br />
Unless the opponent is calling tiles randomly, otherwise these sort of behaviour is no different from declaring riichi.<br />
<br />
<u><b>2) Opponent's discards</b></u><br />
The most important thing to note is whether or not the opponent has <span style="color: blue;">discarded tiles related to major yakus</span>. Example:<br />
a. Discarding manzu when making a manzu chinitsu.<br />
b. Discarding a middle tile dora after calling middle tiles.<br />
c. Discarding chun while it's a live tile, after having pon on haku and hatsu.<br />
<br />
When situations like these occur, the opponent is probably in tenpai, at the very least in iishanten. Also, <b>if the opponent continuously discards the tiles they draw or discard a very safe tile, this signifies that the opponent is in tenpai</b>.<br />
<br />
<u><b>3) The action the opponent takes when other players attack</b></u><br />
This sort of tile reading is useful when playing in high level games.<br />
You can tell that an opponent with melded sets is in tenpai, when he takes the following actions even when another player takes an obvious offensive stance.<br />
a. continue to call on tiles<br />
b. continue to discard dangerous tiles <br />
<br />
Of course, knowing whether or not the opponent is in tenpai is just the first step. The next step would be determining the value of the hand and the area the waiting tiles are in. This will be discussed in the next article. <br />
(To be continued.)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com1tag:blogger.com,1999:blog-5359455608998331474.post-30807893318040718862012-02-05T12:53:00.000+08:002012-02-13T19:58:53.023+08:00Defence theory(10): What do you do when there's no safe tiles?Source: <a href="http://blog.jpmahjong.net/read.php/549.htm">http://blog.jpmahjong.net/read.php/549.htm</a><br />
<br />
The betaori techniques mentioned before, were all assuming that you had enough safe tiles. Usually, when someone is attacking and you hold two or more safe tiles, there's a high chance of avoiding a deal-in. The reason is that once you have discarded two safe tiles, chances are there'll be more safe tiles. According to statistics, when your hand is closed, <b>there's a 50% chance of drawing a safe tile</b>. (Including the tiles discarded by the player in riichi or other players, and the tiles you draw and confirmed to be safe tiles.)<br />
<br />
Even so, there are times when we have no safe tiles when someone is attacking. The following text will introduce a few commonly seen methods.<br />
<br />
<u><b>1) Dismantle anko/toitsu</b></u><br />
This is the most commonly seen method, mainly based on the idea that "betting on a dangerous tile can buy a few safe tiles".<br />
<br />
Sometimes, just when we've just dealt with all the word tiles, the opponent declares riichi.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://4.bp.blogspot.com/-FcGKeRNtJsk/Ty3zKIvngbI/AAAAAAAAAFI/erHDvq1pjJA/s1600/image17.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://4.bp.blogspot.com/-FcGKeRNtJsk/Ty3zKIvngbI/AAAAAAAAAFI/erHDvq1pjJA/s1600/image17.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">(In riichi)</td></tr>
</tbody></table>
If your hand is a ryanshanten hand, it is rather far-fetched to attack a player who's already in tenpai, going to betaori here is the norm.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-FrfXvCDkKCk/Ty30Y0AgIAI/AAAAAAAAAFQ/qMithqbZTik/s1600/image18.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="45" src="http://2.bp.blogspot.com/-FrfXvCDkKCk/Ty30Y0AgIAI/AAAAAAAAAFQ/qMithqbZTik/s320/image18.jpg" width="320" /></a></div>
<br />
However there are no safe tiles here. In normal situations, I would recommend discarding the half suji-pai of 6 wan. Betting on a dangerous tile can buy a few safe tiles. If there are no safe tiles even after discarding finish all three 6 wan(the probability is very low), you can still rely on suji-pai of 3 wan. By the way, if the attacking player discards 9, and if you have 3 and 6 in your hand, discarding 6 is <a href="http://en.wikipedia.org/wiki/Tesuji#Tesuji">tesuji</a>.<br />
<br />
This idea remains useful even when there are safe tiles available.<br />
When someone declares riichi, and your hand is like this:<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://3.bp.blogspot.com/-L5Tb8Eih9wM/Ty4CuyF8bJI/AAAAAAAAAFY/X51bTeIUqtA/s1600/image19.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="40" src="http://3.bp.blogspot.com/-L5Tb8Eih9wM/Ty4CuyF8bJI/AAAAAAAAAFY/X51bTeIUqtA/s320/image19.jpg" width="320" /></a></div>
<br />
The only suji-pai is 3s, and 1 pin is one chance, while the rest are not suji-pai. As the suji-pai is a dora soba, you might not feel comfortable in discarding it, therefore you can discard the riskier 1 wan. Once 1 wan passes, you won't have to worry about not having any safe tiles. You're already in a dangerous situation, and if you discard 3 sou first and don't get any safe tiles in the next discard, you'll still have to discard 1 wan. Compared to discarding 1 wan before, 3 sou becomes a pointless risky tile.<br />
<br />
<u><b>2) Kanzen Shinko</b></u><br />
When you don't have any safe tiles, going into kanzen shinko is also a choice, especially when you have called any tiles. You have to understand, <span style="color: red;">that the lesser the amount of tiles in your hand, the lower the chances of new tiles appearing for the next round of discards</span>. Of course, whether or not to attack, is also dependent on the points situation.<br />
<br />
[First image in <a href="http://blog.jpmahjong.net/read.php/549.htm">http://blog.jpmahjong.net/read.php/549.htm</a>]<br />
<br />
Like the example above, there's only one suji-pai of 3 wan, it is logical to discard 8 wan or 7 sou to kanzen shinko. Even if you discard 3 wan, you'll probably need to discard more dangerous tiles in the future. Even though the chances of winning is low, but the value of the hand is high enough and you're the dealer. Summoning up your courage and attack seems to be the only choice here.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-30520404034317721482012-02-04T12:02:00.001+08:002012-02-04T12:06:23.442+08:00Defence theory(9): Important points of betaori(Part 2)Source: <a href="http://blog.jpmahjong.net/read.php/547.htm">http://blog.jpmahjong.net/read.php/547.htm</a><br />
<br />
The aim of this article is to develop your perception towards betaori, while also introducing some high level techniques.<br />
<br />
[First image in <a href="http://blog.jpmahjong.net/read.php/547.htm">http://blog.jpmahjong.net/read.php/547.htm</a>]<br />
<br />
It's south round first hand in the above picture, kamicha declares riich on the 8th discard, what should Ton do? <br />
First you should find out, is this a situation to go into betaori for?<br />
<br />
Ton gained a considerable advantage from the east round, <span style="color: red;">the important thing to do now is to reduce the amount of points loss in the south round</span>. Even though the pinfu dora 2 is a good hand, but it's only ryanshanten, in a situation where you're leading, I believe going into betaori is a correct choice.<br />
<br />
Once you know you need to go into betaori, the next step would be finding the safe tiles. The genbutsu of kamicha are currently 4 pin and chun. While 1 wan is the safest tile outside of genbutsu. (1 wan is a no chance tile, don't forget the 2 wan that was pon.) I'll take the opportunity to mention, a lot of beginners believe that just because kamicha discard 1 and 3 sou, 2 sou would be a safe tile. This is a misconception.<br />
<br />
Then, the genbutsu of 4 pin and chun, which should be discarded first? I will first discard 4 pin, there are two reasons for this.<br />
1) Currently, 4 pin is an <span style="color: blue;">absolutely safe tile</span>. (Kamicha has discarded 4 pin before, therefore he/she cannot win on the 4 pin.)<br />
2) Another reason for discarding 4 pin, is expecting shimocha to call on it and continue to attack. From this current situation, kamicha who is in third is in riichi, shimocha who is in fourth won't go into betaori easily. Deliberately letting shimocha call your tile, is to cause a situation where both players attack each other, increasing the chances of dealing in for both players. <span style="color: red;">In other words, decreasing your chances of dealing in.<span style="color: black;"> </span></span><span style="color: black;">This is a practical high level technique.</span><br />
<br />
A lot of readers may feel that discarding chun and maintaining the taatsu is still commendable. However everyone has to understand this, to reach tenpai with this hand, <b>you need to gamble on discarding 2 sou and 9 sou, both of which are not suji-pai</b>. With this situation in points, this is too much of a gamble.<br />
<br />
Betaori, is not just about finding a few genbutsu and discarding them. One of the important points of an excellent betaori technique, is to take stock of the situation, list out an accurate discard order, and genuinely decreasing your chances of dealing in to the lowest.<br />
<br />
I hope that everyone can continue to improve their betaori.<br />
<br />
(To be continued.)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-9449832278444758662012-02-03T20:53:00.005+08:002012-02-03T20:53:54.710+08:00Defence theory(8): Important points of betaori(Part 1)Source: <a href="http://blog.jpmahjong.net/read.php/544.htm">http://blog.jpmahjong.net/read.php/544.htm</a><br />
<br />
The previous article spoke specifically about betaori's timing, the next two articles will go into detailed explanations about the important points of betaori and techniques.<br />
<br />
Again, betaori is <span style="color: red;">totally giving up your chances of winning, reducing your chances of dealing in to the lowest.</span> Hence at this stage, especially those who are new to betaori, don't be afraid to dismantle good mentsu or taatsu, or attempt to reach tenpai or even try to win.<br />
<br />
The text below will start to explain the related points.<br />
<br />
<u><b>1) Betaori starts with the safest tile</b></u><br />
If the reader paid attention to the previous articles, then you should know that this is not the first time I've said this. As this is an important principle in betaori, I'll patiently repeat it once more.<br />
<br />
[First image in <a href="http://blog.jpmahjong.net/read.php/544.htm">http://blog.jpmahjong.net/read.php/544.htm</a>] <br />
<br />
Shimocha declares riichi, it's obvious that this situation requires betaori. A hand in suushanten, if it's because [I am the dealer] and recklessly try to attack, you'll only lose even more badly.<br />
When you're in betaori, you better <span style="color: blue;">prepare to sort out the safe tiles in your hand in order</span>.<br />
<br />Which are the safest tiles now?<br />
The safest tile is of course ton, the genbutsu of shimocha. As haku is already pon by toimen, therefore it's a 100% safe tile. At the same time, don't forget that 7 pin was pon by shimocha, therefore it's also a genbutsu.<br />
What's the fourth safest after that? A lot of people think that it's suji of 9 wan... The correct answer is 9 pin. Toimen pon the 7 pin, and the last 7 pin is in your hand, in other words, 9 pin is a no chance tile. There is also two other 9 pin discarded, 9 pin can only be a tanki wait, it is the fourth safest tile. 9 wan is a suji-pai, but there are no other 9 wan discarded, therefore it's degree of safety is lower.<br />
<br />
Therefore the betaori discard order in this situation is: Ton/haku -> 7 pin -> 9 pin -> 9 wan -> 9 wan<br />
<br />
<span style="color: red;">The most common mistake by beginners, is over reliance on suji-pai</span>, discarding 9 wan thinking that it's relatively safe. This is a bad habit, because it is not rare to deal in over careless mistakes. The thing to note is, after discarding genbutsu for 2 turns, more genbutsu could appear, and you may not even need to discard 9 wan. Don't underestimate such triviality. During a few hundred games you play, there could be a few hundred hands you need to go into betaori for, and a stricter betaori could cause you to deal in a few hands lesser. <br />
<br />
<u><b>2) Try to hold on to safe tiles common to multiple players</b></u><br />
On the other hand, <span style="color: blue;">once your hand holds several genbutsu, and you decide to go into betaori, I will first discard genbutsu of number tiles. <span style="color: black;">The reason is that if another player starts to attack later, then your word tiles could be used to defend against both players. The danger about holding genbutsu of number tiles is, once another player declares riichi, this safe tiles will turn into dangerous tiles.</span></span><br />
<span style="color: blue;"><span style="color: black;"> </span> </span><br />
[Second image in <a href="http://blog.jpmahjong.net/read.php/544.htm">http://blog.jpmahjong.net/read.php/544.htm</a>]<br />
<br />
The situation is currently in betaori. The 8 pin discarded by kamicha is a new genbutsu. You should discard 8 pin here, and keep the xia, which is relatively safe to the other players. In the real game, toimen discarded 3 sou and declared purse riichi. This xia became an important safe tile.<br />
<br />
Let's cite another difficult example.<br />
[Third image in <a href="http://blog.jpmahjong.net/read.php/544.htm">http://blog.jpmahjong.net/read.php/544.htm</a>] <br />
<br />
Shimocha is in riichi, you need to go into betaori here too. Although 8 wan and 9 pin are both genbutsu, but you should discard 8 wan here. The reason is that toimen discarded 6 pin, 9 pin is a relatively safe suji-pai. If toimen declares pursue riichi afterwards, you still have a safe tile to discard.<br />
There are people who assume that there is no difference between 8 wan and 9 pin, this is a casual thought. Betaori is not just discarding the genbutsu of the player who declared riichi. <span style="color: red;">A person who is excellent in betaori, will take careful note of the order he discards his tiles.</span> <span style="color: black;">Remember, your enemy is not only the one who declared riichi.</span>Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-82275953844356130632012-02-02T00:35:00.001+08:002012-02-05T15:23:31.928+08:00Defence theory(7): Requirement for betaoriSource: <a href="http://blog.jpmahjong.net/read.php/542.htm">http://blog.jpmahjong.net/read.php/542.htm</a><br />
<br />
We've prepared the absolute requirement for betaori. For the next 2 to 3 articles, we'll be explaining how to betaori using actual games.<br />
This article will be explaining when we should go into betaori. (To a certain degree, this is a discussion about offence and defence for beginners.) Look at the game below.<br />
[First image in <a href="http://blog.jpmahjong.net/read.php/542.htm">http://blog.jpmahjong.net/read.php/542.htm</a>]<br />
<br />
Kamicha declared riichi at the fifth discard, what should you do?<br />
Discard west here, just for this discard. Someone who discards anything else, might not have the qualifications to discard on the level of "Special". (Translator note: My guess is that the author is referring to a ranking called "Special".)<br />
The hand is currently in yonshanteen, while kamicha is in tenpai, the situation is like you're 50m behind someone in a 100m race, don't even think of trying to catch up. Additionally, avoiding a deal-in while trying to reach tenpai is a difficult problem.<br />
<br />
Betaori is the only way for this sort of tiles.<br />
[Oh, let's discard 1 pin and see what's going to happen next.] Thoughts like this, should be avoided at all cost. You must discard the safest tile, xia here.<br />
Remember, <span style="color: blue;">when in betaori, start with the safest tile</span>.<br />
Usually, <span style="color: red;">if you want to pursue riichi or challenge someone in tenpai, you need to have a iishanten or better with a good shape</span>. For anything ryanshanten or below, unless there are no safe tiles or the situation is special, please do not hesitate going into betaori.<br />
<br />
In Japan, some high quality tactics discussion recommend beginners to employ a simple offence and defence baseline.<br />
<br />
<div style="text-align: center;">
<b>Once an opponent declares riichi, if your hand is already in tenpai, then attack immediately(or pursue riichi), or else go into betaori.</b></div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: left;">
Do not underestimate this method of judgement, if everyone can execute this perfectly, going up to 3 dan, or even entering "special" might not be a problem.</div>
<div style="text-align: left;">
<u><br /></u></div>
<div style="text-align: left;">
<u><b>Shanten number, is more important than hand value</b></u></div>
<div style="text-align: left;">
The largest factor in deciding whether or not to attack, <span style="color: red;">is your own shanten number, instead the hand value is a secondary factor. </span><span style="color: black;">Because, if you win, your opponent's chance of win disappears at the same time. A hand worth 3900 points in tenpai,</span> is better to attack with than an iishanten hand worth 8000 points. </div>
<div style="text-align: left;">
[Second image in <a href="http://blog.jpmahjong.net/read.php/542.htm">http://blog.jpmahjong.net/read.php/542.htm</a>]</div>
<div style="text-align: left;">
The hand in the image above has a high chance of becoming a mentanpin dora 1 mangan hand. But if shimocha declares riichi, and your hand is still in ryanshanten, you should immediately go into betaori.</div>
<div style="text-align: left;">
In this discard, discarding the live tiles xia or haku is very dangerous. You should discard the two genbutsu, and go into betaori. Most beginners find that it's very unnatural to go into betaori here, but having the courage to go into betaori with such good tiles, is an important step to improving.</div>Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-18999093259249180182012-01-31T15:51:00.000+08:002012-02-06T22:07:57.955+08:00Defence theory(6): Tile risk tableSource: <a href="http://blog.jpmahjong.net/read.php/541.htm">http://blog.jpmahjong.net/read.php/541.htm</a><br />
<br />
Theories regarding kabe and suji have already been covered, next will be a summarization of the different degree of safety of tiles, making it into a risk table.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-FwxfxxlhjtQ/Tyeq9_OhyXI/AAAAAAAAAEE/5UQfgVMTzQk/s1600/Risk+table.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="350" src="http://2.bp.blogspot.com/-FwxfxxlhjtQ/Tyeq9_OhyXI/AAAAAAAAAEE/5UQfgVMTzQk/s400/Risk+table.jpg" width="400" /></a></div>
<br />
The risk ordering above, should be memorized by beginners, because the ordering above decides what tile to discard first when in betaori, which heavily affects deal-in rate.<br />
<br />
<u><b>Risk factors</b></u><br />
The table above refers to normal situations, you should consider the following in a real game:<br />
<u>1) dora </u><br />
As there will be more points from waiting on the dora, waits on the dora can be predicted. When the dora is chunchan, the deal-in rate is 1.5-1.6 times of the normal rate, while when the dora is a yaochuhai, the deal-in rate increases to 1.8-1.9 times. Also, the tiles near the dora (a.k.a dora soba) have a 10% increase in deal-in rate.<br />
Hence, <b>the degree of safety of the dora tile, yaochuhai's grade has to drop 3 grades, chunchan has to drop 2 grades</b>. While the dora soba has to drop 1 grade.<br />
<u><br /></u><br />
<u>2) One chance tiles</u><br />
The degree of safety for one chance tiles is roughly between non suji-pai and suji-pai.<br />
<br />
<u>3) The outer tiles of early discarding of 28,37</u><br />
If the attacker discarded 28, 37 number tiles early, the outer tiles will be safer than usual. (For example if the player who declared riichi discarded 8 sou, then 9 sou is relatively safe.) Deal-in rate is 30% lower than usual.<br />
<br />
Also, there are many discard reading books about ura suji, aida yon ken, matagi suji on the market. You might be wondering, why hasn't there been any talk about discard reading.<br />
The reason is because according to game record statistics from 東風莊's super high level tables, this so called discard reading, <b>do not affect the risk of related tiles</b>. So when you're in betaori, it's better to ignore these "skills".Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com6tag:blogger.com,1999:blog-5359455608998331474.post-21229501529405341512012-01-31T15:41:00.004+08:002012-02-02T20:05:15.801+08:00Defence theory(5): KabeSource: <a href="http://blog.jpmahjong.net/read.php/540.htm">http://blog.jpmahjong.net/read.php/540.htm</a><br />
<br />
Assuming your opponent is waiting on 58 wan, his hand must have 67 wan each.<br />
<br />
If you can see(including your hand, discards and called tiles) four 7 wan, then there's no way his hand is holding 67 wan. 8 wan can only be a shanpon or tanki wait, making it safer.<br />
<br />
This 7 wan is known in Japanese mahjong as [kabe], 8 wan is known as no chance tile.<br />
The degree of safety of a no chance tile is equivalent to that of a word tile, therefore the more 8 wan you can see, the safer it is. (If three can be seen, the last one is 100% safe.)<br />
<br />
Also, it is known as [usu kabe] if three 7 wan is seen, 8 wan is known as one chance tile. The risk of one chance is between a suji-pai and non suji-pai. The important thing to note is, <span style="color: blue;">as the game continues, the degree of safety for one chance gets lower and lower</span>, as the chances of drawing the last 7 wan gets higher and higher.<br />
<br />
<u><b>Fusion of kabe and suji</b></u><br />
Effective use of kabe and suji can help determine more safe tiles, listed below is a few common examples:<br />
<br />
a) If 4 and 7 are both kabe, then 5 and 6 are the same as word tiles, they can only be tanki or shanpon waits.<br />
b) If 9 has been discarded, 6 is half suji-pai. If 4 is a kabe, because 45 cannot form with 6, the degree of safety for 6 is equivalent to double suji-pai. It would be even better if 5 is a kabe, as 6 is on the same level as suji of 1 and 9.<br />
<br />
Kabe and suji have roughly been discussed. The next time will be introducing tile risk table.<br />
(To be continued)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-1260104860552004032012-01-31T14:22:00.000+08:002012-02-02T20:05:15.756+08:00Defence theory(4): Suji-paiSource: <a href="http://blog.jpmahjong.net/read.php/539.htm">http://blog.jpmahjong.net/read.php/539.htm</a> <br />
<br />
Next I'll introduce two very important concepts in Japanese mahjong: suji-pai and kabe.<br />
<br />
In Japanese mahjong, 60% of tenpai in riichi are ryanmen waits. Therefore, if it is certain that some tiles cannot be ron by ryanmen tenpai, they are considered to be safe.<br />
<br />
<u><b>Suji-pai(Degree of safety: S~B)</b></u><br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://3.bp.blogspot.com/-UYa0dvT0xHQ/Tyd_7_Huy2I/AAAAAAAAAD8/9m85k_xvKqU/s1600/image16.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://3.bp.blogspot.com/-UYa0dvT0xHQ/Tyd_7_Huy2I/AAAAAAAAAD8/9m85k_xvKqU/s1600/image16.jpg" /></a></div>
<br />
We'll use the previous riichi image as an example. If the player who declared riichi discards 5 pin, <span style="color: blue;">then if you discard 8 pin, then the opponent can't ron on your discard even if he holds 67 pin and is waiting on 58 pin.(According to the furiten rule.)</span> To ron on 8 pin, the only possibility is shanpon and kanchan, therefore the probability of dealing in is lower. Similarly, 2 pin, 9 pin, 9 sou are safer due to the fact that they're suji-pai.<br />
<br />
If 4 is discarded, 1 and 7 are the suji-pai.<br />
If 5 is discarded, 2 and 8 are the suji-pai.<br />
If 6 is discarded, 3 and 9 are the suji-pai.<br />
<br />
We normally remember these three groups as <span style="color: red;">1-4-7, 2-5-8, 3-6-9</span>.<br />
It is worth noting that, even if 1 sou is discarded, 4 sou is not a suji-pai, as he could still be waiting on 4-7 sou.<br />
<br />
By the same token,<br />
If 1 and 7 is discarded, 4 is a suji-pai.<br />
If 2 and 8 is discarded, 5 is a suji-pai.<br />
If 3 and 9 is discarded, 6 is a suji-pai.<br />
<br />
The 456 here is called <b>double suji-pai</b>. If only one of the suji is discarded, it is called <b>half suji-pai</b>.<br />
<br />
<u><b>Difference between degree of safety for different suji-pai</b></u><br />
There are many suji-pai introduced above, but their degree of safety are all different.<br />
<br />
For example, the suji-pai of 9 pin, as the chances of ryanmen is eliminated, then <span style="color: blue;">it can only be tanki or shanpon tenpai, the chances of safety is similar to word tiles.</span> If you see two of the 9 pin already discarded, 9 pin can only be hell wait, then the degree of safety is similar to that of tanki word tiles. If you can see three of the tiles, then it's 100% safe.<br />
Hence, suji-pai of 1 and 9 can be said to be the safest among all suji-pai.<br />
<br />
For suji-pai of 2 and 8, not only can it be shanpon and tanki, it can also be kanchan for 13 and 79. Therefore the degree of safety is lower.<br />
For suji-pai of 3 and 7, there can be penchan of 12/89 and kanchan of 24/68. Therefore, the risk is much higher. The kanchan could even be part of a tanyao hand, increasing the degree of harm to you.<br />
As for the double suji-pai of 456, as there can only be kanchan, the degree of safety is similar to suji-pai of 28.<br />
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In summary, the degree of safety for suji-pai in order is:<br />
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<b>Suji-pai of 19 >> Suji-pai of 28 == Double suji-pai of 456 > Suji-pai of 37</b><br />
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The next round will be about another important concept: Kabe.<br />
(To be continued)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0tag:blogger.com,1999:blog-5359455608998331474.post-20448855303505738672012-01-31T10:40:00.000+08:002012-02-02T20:05:15.794+08:00Defence theory(3): GenbutsuSource: <a href="http://blog.jpmahjong.net/read.php/537.htm">http://blog.jpmahjong.net/read.php/537.htm</a> <br />
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From this article onwards, I'll slowly explain the technique of betaori. For the sake of convenience, let's assume only one person is in tenpai.<br />
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Firstly, the most important principle in betaori is:<br />
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<div style="text-align: center;">
<span style="font-size: large;"><span style="color: red;">According to how safe a tile is, discard in order starting with the safest tile</span></span></div>
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Note, <span style="color: blue;">once you decide to betaori, you should discard a tile based on how safe it is, even if it means discarding your mentsu or shuntsu.</span></div>
On an average, betaori happens 30%-40% of the time, therefore a person's betaori skill will directly affect their score. <br />
Today, we'll introduce a few highly safe tiles.<br />
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<u><b>Genbutsu(Degree of safety: SS)</b></u><br />
Reusing the previous example:<br />
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<div class="separator" style="clear: both; text-align: center;">
<a href="http://2.bp.blogspot.com/-FQHL3dibNsg/TydPE3U8F_I/AAAAAAAAAD0/ZIyLVIwWFKs/s1600/image16.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-FQHL3dibNsg/TydPE3U8F_I/AAAAAAAAAD0/ZIyLVIwWFKs/s1600/image16.jpg" /></a></div>
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The tiles here discarded by the player who declared riichi, including 56 pin, 7 wan, 6 sou etc, are known as genbutsu.<span style="color: blue;"> They're 100% safe </span><span style="color: blue;">to the player who declared riichi.</span> Even if the riichi is waiting for the tiles that the player discarded himself, because of the furiten rule, the player who declared riichi won't be able to win on your tile.<br />
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Similarly, any tile discarded after the riichi is genbutsu. <br />
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<u><b>The fourth word tile(Degree of safety: SS)</b></u><br />
Of course, if there is any word tile that has been discarded three times, it should be 100% safe to discard unless it's kokushi musou. As kokushi musou has unique discards, and is easily detected by others, added to the fact that the probability of kokushi musou is low, it's degree of safety is on the same level as genbutsu.<br />
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<u><b>Tiles discarded by the player before you in the same turn</b></u><u><b>(Degree of safety: SS)</b></u><br />
Due to the furiten rule, tiles discarded in same turn by the player before you is also 100% safe.<br />
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Basically, these three are the only absolutely safe tiles, I'll continue to introduce other safe tiles based on the degree of safety.<br />
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<u><b>Exhausted word tiles</b></u><u><b>(Degree of safety: S)</b></u><br />
Word tiles that have been discarded twice, even if there's a chance of a hell tanki wait, are relatively safe tile. Firstly, there is little chance of a player who declared riichi to be on a hell tanki wait, because they won't be able to win if the last tile is in the dead wall. Also a word tile waiting on tanki is easy to change, and most would change to a better tenpai before declaring riichi.<br />
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(To be continued)Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com3tag:blogger.com,1999:blog-5359455608998331474.post-69132356351533254592012-01-30T23:32:00.002+08:002012-02-15T21:48:02.757+08:00Defence theory(2): Overview on defending in Japanese mahjongSource: <a href="http://blog.jpmahjong.net/read.php/536.htm">http://blog.jpmahjong.net/read.php/536.htm</a><br />
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Starting from this article, I'll begin to talk about Japanese mahjong's defence theory. I will first introduce common defence tactics in Japanese mahjong.<br />
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The goal of defending is rather simple, just don't discard the tile your opponent is waiting on. To achieve this, everyone might have thought: [As long as you know the tile your opponent is waiting on, you won't deal in.] Alright, now I'll invite everyone to guess, what is the player in the picture below waiting on?<br />
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<a href="http://4.bp.blogspot.com/-p_1C9rSVRwo/Tya3rq2YOLI/AAAAAAAAADs/EQ7fTzVxx9I/s1600/image16.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-p_1C9rSVRwo/Tya3rq2YOLI/AAAAAAAAADs/EQ7fTzVxx9I/s1600/image16.jpg" /></a></div>
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<u><b>"Reading point" is impossible!</b></u><br />
The numerous mahjong books available all have theories related to discard reading, where they attempt to read the hand of the opponent just based on the discards. In most mahjong mangas, there are scenes where the opponent's waits are accurately read.<br />
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However, reality is cruel. <span style="color: red;">A situation where you can accurately read the waiting tiles(a.k.a "reading point") of an opponent just by reading the discards is impossible.</span> <span style="color: black;">The discard reading skill mentioned in mahjong strategy books could be considered impressive with just an accuracy of 30%</span>. Part of the outdated theories have also been proven to be wrong. (Such as ura-suji, aida yon ken etc)<br />
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If the reader hopes to learn perfect defence in the future theory discussions, like the emperors of old who tried to seek immortality, you'll only be disappointed.<br />
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<u><b>The essence of defence in Japanese mahjong, identifying safe tiles</b></u><br />
There is no immortality drug in this world, but there are ways to live longer. There are no techniques that allow you to see through the wait of your opponent, but there are many ways to avoid dealing in, and they are not difficult to learn.<br />
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The amount of games I've played in MFC are around 4800, with a deal-in rate of 12.6% in over 20000 hands. (winning rate of 25.1%) Compared to other so called high level Yellow Dragon players who have the similar winning rate as me, my deal-in rate is on an average at least 2% lower. But in my 4 years of playing MFC, I've never tried to guess the waiting tiles of my opponent. This proves that in order to defend well, you don't need any supernatural powers.<br />
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In order to defend well in Japanese mahjong, all you need to do is to find the safe tiles. Like the example in the picture above, I believe most of the readers are unable to guess the waiting tiles. This hand has a shanpon wait of 3 sou and 8 pin. But what we can be sure of is, you definitely won't deal in by discarding 56 pin, 7 wan and 6 sou.<br />
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If you don't follow highly accurate(with at least 98%) safe tile theories, but follow those unorthodox theories with only 20-30% accuracy, it will only end badly for you.<br />
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<u><b>Strategies when opponent is in tenpai</b></u> <br />
Against an opponent's riichi, the strategies that you can employ, are the following:<br />
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1) Betaori: Totally giving up any chance of winning, and at the same time decreasing the chances of dealing-in to the minimum. This is the most commonly used tactic. In this series of articles, more than half the text will be covering this area.<br />
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2) Uchimawashi: While discarding tiles that have a good chance to be safe, continue to proceed to tenpai. If the tiles that you draw continue to be not useful, you can consider going into betaori. But if you want to be able to perform well here, you need to have good judgment, this can be difficult for beginners to grasp, therefore this article will only be briefly discussing this.<br />
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3) Kanzen Shinko: You'll discard any tile without hesitation, in simple terms you're ignoring your opponent's tenpai. The important thing to note is, even if the chance of winning is low, it does not mean that you shouldn't go into kanzen shinko. It's fine as long as you attack reasonably. (Translator note: The original text by the author didn't make sense. Therefore, I assumed that it's a typo error and changed it to what I think he really meant.)<br />
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Of course there are strategies to deliberately deal in, but the amount of them is too low.<br />
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The biggest problem with beginners, <span style="color: red;">is that they go into kanzen shinko and ignore uchimawashi too often, and rarely go into betaori.</span> They feel that they'll go into last place if they don't win the current hand. However in Japanese mahjong, as the losses from dealing into riichi is not small(riichi has ippatsu, chance of ura dora, menzen, and many other yaku), if you know your chances of winning is small, you should retreat and minimize your losses.<br />
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The next article will go into details on how to find safe tiles.Hongyihttp://www.blogger.com/profile/04544331931259072258noreply@blogger.com0