Ura Dora Strategy

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Ura Dora Strategy

Post by HotelFSR » Fri Apr 17, 2009 4:02 pm

When I started playing I didn\'t like the idea of ura-dora, although I do enjoy them now.

However, I definitely understand why they are not included in A-Rules. I feel like when ura-dora are included in the game, you almost always want to reach when the opportunity presents itself because the potential reward is so high. It\'s also quite often more likely that you will get more han by shooting for ura-dora (and more efficiently so) than you would by not calling reach in order to wait and improve your hand.

Without ura-dora you have to think a lot harder about whether you want to reach. Presumably when you are up against really good players you\'ll still want to think twice about reaching (even with ura-dora in the equation) because their defense will make such a big difference. However, this is undermined by tsumo because even against strong opposition the it can easily combine with reach and ura-dora to turn even a trash hand into a huge one, making it a risk very often worth taking. Guess that must be why A-Rules have done away with ura-dora?

Follwing on from my other post here about red fives (about how they actually decrease variance in hand values, not just inflate them, by smoothing out the Han size distribution) I almost wonder whether A-Rules should reinstate red fives.

Assuming that they do indeed reduce variance, that is, counterintuitive though it may be. Ultimately, I\'m not yet entirely sure the theory is correct.

Looking at my Mahjong Fight Club stats does seem to suggest it is correct.

Any thoughts?

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Re:Ura Dora Strategy

Post by Denizar » Fri Apr 17, 2009 6:31 pm

Removing ura-dora from the game, in my opinion, wouldn\'t add to the strategy at all. The strategy in riichi mahjong is more focused on not dealing into opponents hands than making hands that are more valuable. After all, the tiles that come to you are random, and the hand you are making depends much on luck. On the other hand, not dealing into a riichi requires more skill. If ura-dora were removed, the threat of riichi\'s would diminish and so would the importance of defensive play.

Ura-dora also makes riiching more rewarding. Without ura-dora, why would you risk yourself by calling riichi just for one extra han? I wouldn\'t even consider it. And if you need to call riichi because you don\'t have the minimum 1 han, is that hand even worth winning? Of course you can have a hand with riichi and several dora, but thats pretty rare...

Its true and annoying that sometimes a new player will riichi and tsumo, then get several ura dora making a monster hand, but I think that thats just fine. Luck is always a part of mahjong.

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Re:Ura Dora Strategy

Post by HotelFSR » Fri Apr 17, 2009 6:52 pm

I\'m assuming you didn\'t know that JPML (the Japanese professional league that Garthe and Jenn play in) plays with a ruleset that does not use ura-dora. They call this ruleset A-Rules, and they also do not use kan dora, kan-ura dora, ippatsu or red fives.

Players in that league, however, as far as I\'m aware, still use Reach a whole lot. It\'s all about planning- even this \'one Han\' can be the difference between a 4000 point hand and a Mangan. If you \'wouldn\'t even consider it\' as you say, I doubt you\'d get far in that league!

While not dealing into hands is one of the biggest skills in the game, it also takes skill judging when to reach and when not to. It\'s a more fine-tuned decision with A-Rules, whereas it\'s generally more of a no-brainer with normal rules (i.e. using ura-dora), which the JPML refers to as B-Rules. Reaching also has value in that it can cause players to fold, and has potential to be used as a bluff.

Yes, luck is a big part of the game, and yes new players can get very lucky. That\'s as it should be, and I have no problem with it.

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Re:Ura Dora Strategy

Post by Denizar » Fri Apr 17, 2009 7:02 pm

I see. Do you have any further information on the A-rules? I\'d like to know more about it.

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Re:Ura Dora Strategy

Post by HotelFSR » Fri Apr 17, 2009 7:05 pm

Not in English. However, what I mentioned above is basically everything. No ura dora, kan dora, kan ura dora, ippatsu or red fives.

If you can read Japanese, have a look at the JPML official rules page:

http://www.ma-jan.or.jp/guide/game_rule.php#15

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Re:Ura Dora Strategy

Post by Denizar » Fri Apr 17, 2009 7:14 pm

I\'m not that good at Japanese yet.. sadly..

How many games do they play in the league? Or, how many \"kyoku\" does a game last?

In short games I can totally understand why they\'d want to get rid of those extra han rules. In a long game, the difference in skill becomes more evident, but in short games its really about who gets more lucky. So if they don\'t have time to play at least 3-4 Han Chan for each game in the league, it makes sense to remove the all those doras. Right?

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Re:Ura Dora Strategy

Post by HotelFSR » Fri Apr 17, 2009 7:17 pm

Nope, the A-Rules are for hanchan (full game with dealer continues) and they play a whole lot of games in the league spread throughout the whole year!

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Re:Ura Dora Strategy

Post by Benjamin » Sun Apr 19, 2009 3:48 pm

Ura-dora certainly adds variance. Instead of having to aim your hand at a certain yaku in order to get a guaranteed 3900 pts, for example, you can instead riichi and hope you get lucky. Another way of explaining it I\'ve heard is that strict rules don\'t allow instances where you can\'t tell how much your hand will be worth until after you win. Having *controllable possibilities* is allowed (tsumo, winning on one tile and not another), but you can\'t control whether or not you hit ura.

From my own experience, playing with ura-dora definitely makes it easier for beginners to beat experts.

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Re:Ura Dora Strategy

Post by HotelFSR » Sun Apr 19, 2009 6:17 pm

For sure.

It bothers me that for those of us who have to play online there\'s nowhere you can play without ura-dora, as far as I know.

Ron2 allows you to use A-Rules, but only in private games. I seem to remember they were going to set up some kind of online league using A-Rules, however.

Anyone know?

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Re:Ura Dora Strategy

Post by zzo38 » Sun Apr 19, 2009 7:55 pm

All I know is the software I am working on called XUL mahjong, which will allow you to play by any rulesets you want to. And it is license by GNU GPL v3.

And with uradora you can still guess at the probability of uradora (so you can adjust your hand before riichi to adjust the chances of uradora) although you cannot really control it. In the rulesets I have created, uradora is determined in a slightly different way that offers a bit more skill to the game.

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Re:Ura Dora Strategy

Post by KawamuraReo » Mon Apr 20, 2009 9:52 am

Too bad they use automatic tables these days.

If people were like me and didn\'t have automatic tables. If you were skillful enough, you could actually control the ura-dora. Then again it could backfire and this doesn\'t really happen like... ever anymore. Well, except in Mahjong media like movies and such. Bakudan!

Well, realistically speaking, ura-dora not only gives more reason for defensive play but I\'m inclined to believe it rewards more outlandish offensive, manipulating your hand to have multiples of the same tile by, say, transforming an existing hand to a toitoi/chitoitsu/whatever, or manipulating your hand so your pair is the existing dora, well. It certainly rewards players for doing that. This is also taking into consideration luck - even if you take measures to try and get it lucky, you\'re still liable to not get that bonus. It\'s a gamble, but that\'s an obvious part of the game.

Hanchan is 8 kyoku

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Re:Ura Dora Strategy

Post by HotelFSR » Mon Apr 20, 2009 11:16 am

You\'re right about that. I think that\'s probably why ura-dora were invented in the first place- it\'s an ideal pretext for hustlers to switch the tiles.

The problem with ura-dora, as mentioned here, is that they add extra variance, which is why they are not used in the JPML A-Rules for league competition.

zzo38: the software sounds very interesting! would love to hear more about it. what\'s GNU GPL? and will it work online?

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Re:Ura Dora Strategy

Post by zzo38 » Fri Apr 24, 2009 3:04 am

HotelFSR wrote:zzo38: the software sounds very interesting! would love to hear more about it. what\'s GNU GPL? and will it work online?
GNU GPL is a free software license (free as in "free speech", not as in "free beer", but in this case you don\'t have to pay for it either). The license grants you the freedom to use the software, share the software, study how the software works, modify the software, and share your improvements. However, it also requires that anyone else who receives the software from you has the same freedoms as this.

And, yes, the software will work online (and will not be fixed to a single protocol).

The rulesets are written in JavaScript. Most of the rules are built-in to the program already, and then you can add new rules and/or modify existing rules.

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Re:Ura Dora Strategy

Post by HotelFSR » Fri Apr 24, 2009 9:33 am

zzo38:

Sounds great. Keep us posted!

I wonder whether you could help with a technical issue. I\'ve been working on translating the Toupaiou software into English by editing the text straight up in Notepad++. However, it will not run because the filesize gets changed when the string/length is altered. Just switching the string for another of the same size, say, two kanji for two kanji and it will still run. Do you know a way around this problem? Can it be circumvented?

I hope so.

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Re:Ura Dora Strategy

Post by gartheee » Fri Apr 24, 2009 1:46 pm

There are several pros I know of at the top level of our league who play professionally in Mahjong parlors just about every day. For the most part, at work I think they prefer to play games where there are just about as many dora as possible: Ura, Kan, red, and even gold! And another thing they call White-something which one of the White dragons with a diamond in the middle which if you draw after reaching it will be an automatic win no matter what you were waiting for. Despite the fact that these things add variance, I think they feel that their advantage as better players is so good that they would prefer to have this inflation so as to allow them to win the most money possible. It certainly does add excitement to the game. But it can make for some pretty nasty swings when they all go to the guy across the table.

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