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H.G.Muller

Joined: 10 Mar 2006
Posts: 12776
Location: Amsterdam

Post subject: Re: EloStat, Bayeselo and Ordo    Posted: Wed Jun 27, 2012 5:29 am

 Laskos wrote: Yes, but this wouldn't explain some large differences for 90 and 360 games. By the way, if I am not wrong, the result is not exactly 2/3, more like 0.69. And the maximum likelihood is still at 3/4. As for 90 and 360, the results are 0.747 ans 0.749, would be hardly visible in ratings, which, it seems, are compressed in Bayeselo by the artifficial draw rules and priors.

INT from 0 to 1 p^3 (1-p) dp = [ 1/4 p^4 - 1/5 p^5 ] from 0 to 1 = 1/4 - 1/5 = 1/20

INT from 0 to 1 p^4 (1-p) dp = [ 1/5 p^5 - 1/6 p^6 ] from 0 to 1 = 1/5 - 1/6 = 1/30

E(p) = (1/30) / (1/20) = 2/3

The maximum likelihood is indeed at 3/4, but that is not what is significant for making accurate predictions. The prediction error is minimal in the sense of least squares only when you predict the average.

As for the difference betwen 90 and 360 games I would not know, without further looking into what games exactly these were. I suppose this was not a plain match between two opponents, because in that case indeed the effect of the prior should be negligible. Note furthermore that the prior can be switched off in BayesElo.

There is nothing 'artificial' about the 'draw rules' (assuming you mean double-counting of draws). This aspect of the model was confirmed by analysis of the actual computer data. The likelihood of a single draw is indeed equal to that of one win plus one loss within a reasonable accuracy. Any analysis that does not take account of that fact just sucks, in the sense that it expands the rating scale, predicting too extreme results between the top and bottom dwellers.
 Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First
Subject Author Date/Time
Kai Laskos Sun Jun 24, 2012 1:27 pm
Adam Hair Sun Jun 24, 2012 4:38 pm
Kai Laskos Sun Jun 24, 2012 5:46 pm
Edmund Moshammer Sun Jun 24, 2012 6:54 pm
H.G.Muller Sun Jun 24, 2012 7:29 pm
Kai Laskos Sun Jun 24, 2012 8:24 pm
H.G.Muller Sun Jun 24, 2012 8:52 pm
Kai Laskos Sun Jun 24, 2012 9:46 pm
Miguel A. Ballicora Sun Jun 24, 2012 10:05 pm
H.G.Muller Sun Jun 24, 2012 10:44 pm
Miguel A. Ballicora Sun Jun 24, 2012 10:58 pm
H.G.Muller Mon Jun 25, 2012 8:35 pm
Miguel A. Ballicora Mon Jun 25, 2012 9:12 pm
H.G.Muller Tue Jun 26, 2012 6:44 am
Miguel A. Ballicora Tue Jun 26, 2012 3:48 pm
H.G.Muller Tue Jun 26, 2012 4:21 pm
Kai Laskos Tue Jun 26, 2012 9:11 pm
Re: EloStat, Bayeselo and Ordo H.G.Muller Wed Jun 27, 2012 5:29 am
Kai Laskos Wed Jun 27, 2012 9:32 am
H.G.Muller Wed Jun 27, 2012 11:26 am
Kai Laskos Thu Jun 28, 2012 4:48 pm
H.G.Muller Thu Jun 28, 2012 5:17 pm
H.G.Muller Sun Jun 24, 2012 10:36 pm
Kai Laskos Sun Jun 24, 2012 11:00 pm
Adam Hair Mon Jun 25, 2012 2:23 am
H.G.Muller Mon Jun 25, 2012 8:18 pm
Rémi Coulom Mon Jun 25, 2012 8:58 pm
H.G.Muller Mon Jun 25, 2012 9:09 pm
Rémi Coulom Mon Jun 25, 2012 9:16 pm
H.G.Muller Mon Jun 25, 2012 9:43 pm
Rémi Coulom Tue Jun 26, 2012 8:07 am
H.G.Muller Tue Jun 26, 2012 8:31 am
Juan Molina Tue Jun 26, 2012 11:31 am
H.G.Muller Tue Jun 26, 2012 12:22 pm
Kai Laskos Tue Jun 26, 2012 2:15 am
H.G.Muller Tue Jun 26, 2012 6:32 am
Adam Hair Mon Jun 25, 2012 10:01 pm
Sven Schüle Sun Jun 24, 2012 10:21 pm
Kai Laskos Sun Jun 24, 2012 10:54 pm
Sven Schüle Mon Jun 25, 2012 9:22 am
Rémi Coulom Mon Jun 25, 2012 1:51 pm
Kai Laskos Tue Jun 26, 2012 2:09 am
Adam Hair Mon Jun 25, 2012 1:26 am

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