another gameplay question

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or2az
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another gameplay question

Post by or2az » Wed Feb 26, 2014 10:49 pm

Game is hanchan, east 3: After you riichi, do you discard the 3-crak and go for the 2-crak 5-crak wait OR do you discard the
4-crak and go for the 3-crak :east wait?

In this case, since there are three 2-crak and one 5-crak showing on the table, and since both waits have 4 tiles available, I chose to discard the 4-crak and go for the possible additional yaku (east).

BUT WHAT IF the twos and the five were NOT showing on the table, should that affect my decision?
Do you go for the double sided wait with 8 tiles available or the wait with 4 tiles available and a shot at an extra han?

OR...... does the decision depend on other factors, like the score, the round, etc ?
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Re: another gameplay question

Post by Ozball » Thu Feb 27, 2014 3:01 am

To start off with, apologies if this is a bit incomprehensible, I'm still recovering from the flu, and mind isn't as clear as I'd like.

In short, it will always depend on the state of the game, the score, the rounds etc.

Long version: You're actually forgetting one very important factor. If you go for the 3-crak :east wait you actually have the possibility for an extra THREE han. Since if you tsumo the draw you get San Annkou (Three Concealed Triples) for an extra 2 on top of the possibility of the East one. (and the additional one for tsumo as well, so 4 possible han extra if you tsumo the :east) But it will all come down a bit to your style of play. In theory if you want a better chance at winning at a lower score then the 2-crak 5-crak wait would be better (in the situation you described where you can't see any of the other tiles, meaning you have more tiles you're waiting on). But if you want the higher score then the 3-crak :east is better due to reasons mentioned above.

As it's currently East 3 in the image and you're only just barely in second place I'd probably go for the higher value wait (the one involving East) and hopefully set yourself up for later in the game. Also you've discarded a 6-crak so it's possible that someone could try and play safely with a suji and drop your 3-crak. That's just my thoughts, others might have another point of view.
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Re: another gameplay question

Post by Masa » Thu Feb 27, 2014 10:46 am

I want discard 4-crak with riichi,then expect tsumo.
But I have to care East player, She discarded dora at this turn(already later stage of this round). She took a risk. so that maybe tenpai.
She did not discard dora until now, my guess is she got stand alone dora and has been expected to create dora involded tatsu but could not, then discard. Or discard from 5-crak 6-crak 6-crak (5 is red five) other wise not discrad 6 and try to use as head or expect to become pon. In this case 4-crak is bit risky.
But I can't stop myself to discard 4-crak ...

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Re: another gameplay question

Post by Iapetus » Thu Feb 27, 2014 5:59 pm

Were this aotenjou, halving the wait to go for a 4x or 10x value increase would be delicious. But we have mangan limits in play.

For ron, and tsumo if sanankou was not available, 3s discard riichi is obviously better. Going for the shanpon, you have half the wait with a 50% chance of doubling the score. So the expected value is 25%*1 + 25%*2 = 75% of the expected value of a ryanmen riichi. Furthermore, in the case of riichi-tsumo-ton-aka, the doubled score of 10200 is cut down to 8000 by mangan, so it's even less effective, but that doesn't pertain to this hand.

Now, for sanankou. A plain riichi-tsumo-aka scores 5200 here. Riichi-tsumo-sanankou-aka scores 8000, and riichi-tsumo-ton-sanankou-aka scores 12000. The average of those is 10000, and because the wait is halved, it's effectively 5000. So the two are basically equal.

Now looking at uradora and ippatsu with tsumo.
1 extra han increases the value of the ryanmen riichi by 50%, the tonless sanankou by 50%, and the ton-sanankou by 0%.
2 extra han increases the value of the ryanmen riichi by 50%, the tonless sanankou by 50%, and the ton-sanankou by 33%.
3 extra han increases the value of the ryanmen riichi by 130%, the tonless sanankou by 100%, and the ton-sanankou by 33%.
4 extra han increases the value of the ryanmen riichi by 130%, the tonless sanankou by 100%, and the ton-sanankou by 33%.

A similar analysis on rons shows a similar pattern of the ryanmen wait winning.

Conclusion: the ryanmen wait is better for rons. It combines better with uradora and ippatsu. Even in the plain tsumo case, it's equal. So the ryanmen wait is superior.

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Re: another gameplay question

Post by or2az » Wed Mar 05, 2014 6:30 pm

Here's an interesting one. Since it's a video game and I had a shot at ryanpeko, I called riichi and tossed the 4-bam (the game ended in a draw)
(ryanpeko-twice pure double chow, 3 han, always contains seven pairs, and they do not stack, for those who need to know)
What I'm curious about is, are there any circumstances under which you might think of doing something else?
For example, a real people game, a better wait, the point spread, the 1-bam not showing on the table, another 3-bam showing on the table, etc?
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Re: another gameplay question

Post by Ozball » Thu Mar 06, 2014 4:11 am

Not many cases I'd drop anything else. Dropping the 2-bam and waiting on a 1-crak 4-crak 1-bam could be nice if most of them weren't already out. Even then that would only be in South 4 when I'm ahead and wanting to finish it quickly (waiting on 6 tiles over the 3 you'd be waiting on for your ryanpeikou in an ideal situation).

However I probably wouldn't reach in this situation, there are only 2 more 3-bam left, and West had ponned twice already so could very well be in tenpai. West is also the one who discarded the 3-bam so it's possible someone will discard another as a safe tile and if I reach I might scare off that possibility.
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Re: another gameplay question

Post by or2az » Thu Mar 06, 2014 4:29 am

I see. But why would you probably not reach?
Isn't the chance of getting tsumo and ippatsu along with the riichi worth the risk?
I would still have to discard every tile I draw as I wait for the 3-bam ,and that is just like riichi. (except for the 1000pt wager)
I think that would be a possible total of 6 han if you can get it all. (3+1+1+1).
That's a lot of points and a chance for a really big lead, a 12000 pt haneman, I think?

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Re: another gameplay question

Post by Referee » Thu Mar 06, 2014 5:47 am

No need to warn everyone. Plus, it's late in the hand, so you don't have many choices.

Ryanpeikou tsumo is 30/4 (no pinfu), just short of mangan. Ryanpeikou riichi tsumo you gain 100 points for a wager of 1000.

Ryanpeikou ron is 40/3 (futei, menzen kafu, penchan) for 5200. In this case you can get a bit more for that extra han which yields mangan, but it's still a hell wait with five go-arounds left in the round. 4s and 5s are fresh, so it may very well be used in a hand (likely South, but Oya could have it too) or in the dead wall somewhere.

Also, usually not wise banking on ippatsu tsumo unless your name is Amae Koromo and there are four tiles left.

EDIT: Penchan, not kanchan.

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Re: another gameplay question

Post by or2az » Thu Mar 06, 2014 7:20 am

Ok , I think I understand. Don't even consider ippatsu.
ryanpeikou tsumo or ryanpeiko riichi tsumo, basically no difference, mangan, 8000 pts.
ryanpeiko ron- 5200 points.
ryanpeiko ricci ron- mangan, 8000pts.
So it doesn't pay to riichi because you might get the same points without it, and if you don't, it's only 2800 pts less.
By the way, isn't a hell wait a single instance of a single tile? There are 2 3-bam available. Does that matter?

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Re: another gameplay question

Post by Ozball » Thu Mar 06, 2014 11:02 am

or2az wrote:By the way, isn't a hell wait a single instance of a single tile? There are 2 3-bam available. Does that matter?
I don't think "hell wait" is an official term, so it will come down to how people interpret it. Personally I'd call only 1 possible winning tile a hell wait and anything else a bad wait, but that's just my view, others will likely have other views.
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Re: another gameplay question

Post by Masa » Thu Mar 06, 2014 12:12 pm

There are no official term or written for "hell wait". But the origin of hell wait is following.
1. Single waiting by West tile.
2. Already 2 west tiles are shown in the pond.
These 2 condition are necessary.

For my term, other honor tiles are also ok. but not numeric tiles.

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Re: another gameplay question

Post by or2az » Thu Mar 06, 2014 1:17 pm

This is from Barticles Guide ( page 40 )
地獄待ち [jigoku machi]
A Jigoku Machi (literally a "Hell Wait") is a Tanki wait where two of your three winning tiles are
unavailable so you are waiting on a single instance of a single tile.
I'm not sure if this would apply to my wait in the above example even if there was only 1 tile available (the tanki part), but it seems official to me.
(And then again, it might apply because you are also waiting for seven pairs and a tanki wait is a pair wait even though the hand is not set up as 4 complete sets and a single tile)

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Re: another gameplay question

Post by Masa » Thu Mar 06, 2014 2:46 pm

This is not the case.
The point is "What is the hell ?"

If I have 3b in my hand, I can expect to become tatsu by drawing 1,2,4,5.
I don't discard easy due to it can become mentsu canditate. It is not hell for me. And not sure it is safe or not.
But for honor case, if I see 2 tiles in the pond most likey it will be discared it is useless(can not make pon for mentsu)
and may safe.

It means "It should have been almost safe tile for others, but actually not, it is hell !!"

That's why it called hell wait.

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Re: another gameplay question

Post by Ozball » Fri Mar 07, 2014 1:10 am

or2az wrote:I'm not sure if this would apply to my wait in the above example even if there was only 1 tile available (the tanki part), but it seems official to me. (And then again, it might apply because you are also waiting for seven pairs and a tanki wait is a pair wait even though the hand is not set up as 4 complete sets and a single tile)
Just a quick comment on wait names. A tanki wait is not only where you’re waiting on one type of tile, it is where you’re waiting on one tile to complete your atama/head/pair. You can still be waiting on one type of tile and not have a tanki wait. Eg 1-bam 2-bam would be a penchan wait (or edge wait) on the 3-bam, and a 1-bam 3-bam is a kanchan wait (or gutshot/closed wait) on the 2-bam.

As for what your wait is in the hand above it could be classified as either a penchan wait for ryanpeikou (two double runs?), or a tanki wait for chitoitsu (Seven Pairs). However most rule sets say that a hand will always be interpreted at its highest possible value if there are multiple interpretations, so the hand will be interpreted as ryanpeikou and therefor a penchan wait.

Also the wait that the final hand actually had isn’t actually decided till after the hand if completed (won via either ron or tsumo) as there are cases where the wait can be different depending on the winning tile. For example with 5-dot 5-dot 6-dot 7-dot you are waiting on a 5-dot or 8-dot. But if you win with a 5-dot there are two interpretations of what kind of wait it could be, either a ryanmen wait (or two sided wait) completing the 5, 6, 7 run. Or it could be a tanki wait completing the head of 5, 5. Due to the rule that the hand will always be interpreted at its highest value which wait is actually used will depend on the rest of the hand. If the rest of the hand has all runs, it would be interpreted as a ryanmen wait as that would give you the pinfu (Peace) yaku. However if you had a triple elsewhere in the hand then you would consider it a tanki wait and receive 2 fu for it as it is the higher value wait.
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Re: another gameplay question

Post by Referee » Fri Mar 07, 2014 5:44 am

Or at the very least, not lower. It could well be that the 2 fu don't matter either way, but when it matter (and pinfu isn't involved) it's by being better with the tanki so the general idea still remains, just a clarification.

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