Answer

②Concealed

Commentary

In the last article, I said that if you wait  Ryanmen, you should  call for following Riichi basically.

How about this case ??

Using the statistical possibliity from the last article, let's calculate the rough expected value.

Right side player has 5 dora. Hanneman is confirmed　(Riichi ＋Dora 5).

Following Riichi in the 14th round, the deal in ratio is approximately 15%.

Expected value of Deal in is roughly 13,000 (Haneman + Riichi fee) x 15%＝1950.

Win ratio is roughly 45% x 2700 points (average score for Riichi only in case of hided dora x 3) is 1215.

The rest is the probability of your opponent's self-draw x 3000 or 4000, but this can vary greatly depending on how your opponent waits.

If the opponent wait for Ryanmen , the self drawing probability is 17%, so the probability is approximately 4000 (30% chance of having a concealed dora x 3, which means there is at least one concealed dora) x 17%,= 680.

In addition, this hand has a large number of safty tiles for the Riichi, so we can decide that fold is better for this hand.

However, 

① If you really don't want to be won by the right side player.

② I don't have a safety tile.

If you have such conditions, it is acceptable to go to Riichi even in such an extreme situation.

Even if you can see Dora 5, the difference in numbers is about this much, so you can see how strong Ryanmen following Riichi is. 

Ryanmen ready hand is following Riichi in any situation.

 

Answer

①Riichi

Commentary

Ryanmen ready hand is following Riichi in any situation

The theory of flat hand is always Riichi, but what if another player has already called Riichi first??

With or without a flat hand, following Riichi is the rule for Ryangmen ready hand.

The figure below shows the win ratio and deal in ratio of following Riichi.

The approximate win ratio is always three times the deal in ratio, regardless of the round.

In this case, in particular, I am the dealer, and dealer's score is always 1.5 times higher.

However, even if the player who Riichi'd first is the dealer, the basic rule is following Riichi.

This is because there is an overwhelmingly high possibility that you will win.

Mangan waiting for Ryanmen is basically concealed

 

Answer

②concealed

Commentary

In this hand, it seems that many people think if I call for Riichi and self draw, I can get Heinemann!!

What do the statistics say??

Not only was there no difference regardless of the round, but in the 12th round, the expected score was higher for concealed.

Especially at the end of the game, Mangan waiting for Ryanmen is basically concealed.

Conceal your 5200 hand

 

Answer

②　Concealed

Commentary

 Last article said that the hand only flat hand is always Riichi.

How about all simples without flat hand ??

In this case, Riichi is bad choice.

On the far left column is the average score of winning.

The others are the statistical balance for each round.

There is almost no differences between calling riichi and concealed hand.

One of the reasons is the peculiarity of the score of 5200.

If you call for  Riichi from 5200, the score would not be doubled.

 you would only be paid 1000 points for Riichi fee and 2800 points would be added.

When it comes to round 12, the difference is only 100 points.

Still, even at 500 points, Riichi is still statistically ahead, so I think it's worth considering until round 8. Basically, concealed is the way to go.

Ready hand only Flat hand is always Riichi

 

Answer

①　Riichi

Commentary

Ready hand only Flat hand is always Riichi

This is a Flat-hand-only in the 12th round.

Whether to pay 1000 points riichi fee in order to get  more 1000 points of the hand of 1000 points.

Just remember this.

Flat hand only is always riichi !!

On the far left column is the average score of winning.

The others are the statistical balance for each round.

In the 12th round, even if you keep concealed, in the long run, you will end up in the negative.

Even if you don't win the hand, the effect of letting other players folding is tremendous.

You should also reach at the end of the game to reduce the possibility of your hand dealing in and to increase your chances of getting a no ready hand fine.

Patterns that should be back from ready hand even if it breaks the completed elements

 

Answer

Commentary

Patterns that should be back from  ready hand even if it breaks the completed elements

If you are an advanced player, you don't need an explanation, and most people will discard the 1m.

It is ready hand whether you discard 2m or 4s.

Moreover, drawing 1m,5m, 7m, 3p, 5p, 3s, and 5s gives this hand Flat hand.

And 4m, 8m, 2p, 6p, 2s, and 6s is good form to call Riichi.

Still, we should discard 1m  here.

The reason are that, 

①　Score

②　Whether or not you can call

If you discard 1m, you can back to ready hand by drawing 4m, 8m, 2s, 5s, 3s, 6s.

This can clear  the criteria (6 or more types) for baking from ready hand.

 And, you can call for Riichi by twice or Four times the score ( flat hand, and all simples).

If you draw 4m or 8m, you can get triple sequences.

Next merit is that whether or not you can call.

You don't need to draw 4m, 8m, 2s, 5s, 3s, 6s yourself.

If left side player discard it, you can call for chow for the same amount of points as if you had discarded 2m and 4s.

Acceptance of 6 or more types can back from ready hand.

In addition, if your hand is the above two conditions , you 'should'  back.

Kanchan of 3 tiles left vs Penchan of 4 tiles left

 

Answer

Commentary

Kanchan of 3 tiles left  vs  Penchan of 4 tiles left

Probably many players will drop the Penchan and keep the Kanchan.

The reason for this is that Kanchan can change to Ryanmen.

In reality, however, the possibility of Kanchan changing into Ryanmen is not that high.

The change to Ryanmen requires drawing one of the basic 4 or 5 or 6, and the possibility of drawing the remaining 4 tiles of Penchan is actually much higher.

With 3 7 "not even a single tile in the river", the odds of winning a Penchan are not that low.

If even one tile is visible, the win rate is drastically reduced.

In the case of only one tile of wait, remember that the difference between heaven and hell is whether there is only one in the river or not.