Is it just me, or is the Tenhou randomizer broken?

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Is it just me, or is the Tenhou randomizer broken?

Post by Poochy » Thu Feb 26, 2009 6:14 am

I\'ve been playing Tenhou a lot lately, and I\'ve noticed some oddities in the tile shuffles. For one thing, in about two dozen hands, I don\'t think I saw a single hand where exactly one person went for a Honiisou or Chiniisou without another player trying for the same. Not only was two players simultaneous trying for a Honiisou or Chiniisou surprisingly common, and the sheer frequency where both were going for it in the same suit was baffling, even more so in 3-player games (though this is probably exacerbated by the fact that the 2-8man tiles are removed). This is pure anecdotal evidence, but I just played a 3-player game in which the vast majority of the Sou tiles were dealt in the opening deal, and everybody drew and discarded almost entirely Pin and Honor tiles the rest of the hand because all three of us were trying for a Honiisou/Chiniisou in the Sou suit. And in many hands, I\'ll get an opening draw with about 8-9 tiles in one suit, then never draw a single tile in that suit the whole hand. (In 3-player Mahjong, this often means that one or two of us will have a nearly complete Honiisou, while having another nearly-complete Honiisou in each of our discard ponds.) These oddities come up much, MUCH more often than in Mahjong Fight Club, to the point where I\'ve been able to reliably predict whenever I have a potential Honiisou that one of my opponents is also going for a Honiisou/Chiniisou, and it turns out I\'m right most of the time. In general, I see Honiisou probably ten times more often on Tenhou than on Fight Club.

I recall Garthe mentioning in one article that he sees Chiniisou a lot more often when playing with automatic shuffling tables compared to on Mahjong Fight Club, perhaps because the shuffling tables aren\'t as thoroughly shuffled as MFC\'s randomizer. So, does the Tenhou randomizer have a bug, or is it just my odd luck?

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Re:Is it just me, or is the Tenhou randomizer broken?

Post by HotelFSR » Thu Feb 26, 2009 12:48 pm

Interesting. Hard to say if it\'s just luck or not. Contacting the administrators of Tenhou might yield an answer, or providing a bugreport. Perhaps there is a dedicated section of the site for that like there is on Toupaiou.

Not sure about Tenhou. However, Toupaiou prides itself on having a state-of-the-art Randomizer courtesy of an optimized version of the Mersenne Twister algorithm created by researchers at Hiroshima University.

The Toupaiou site provides this link about it: ... ex-jp.html

It has an english version if you follow the links.

Suffice to say, Toupaiou has an extremely good random number generator!

I wonder what system Tenhou uses, and whether it could actually create any issues such as the ones you mention.

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