Rich Ulrich <[EMAIL PROTECTED]> wrote in message > I think you have suggested the useful way to start - by exploring. > By making the naturalistic description, if one is reasonable. > > First, if there are no players who do better/ worse than chance, > then there is nothing to talk about. So, how much is there? > > Statistically speaking, you might show a "excess of > variation" based on *many* cases with *small* evidences > of bias - that could be tough to study. Maybe interesting, > though, as someone's thesis for methodology. > > But I think you have an actual chance if there are a moderate > number of cases with *large* biases in evidence. Then > you can say, Do they have anything in common? anything > that differs from the non-biased ones? > - Does the *most* extreme match-failure have a > particular feature?
Thanks Rich another idea I have is that I would extra all 'pairs' from the data (or possibly only those who have played a certain minimum number of times), e.g. I get the following from my data: Tom-Dick (27 wins, 14 losses for Tom, average of ELO ratings difference at the time of these matches 289) Dick-Harry (12 wins, 24 losses for Dick, average of ELO ratings difference at the time of these matches -124) For each pair listed above I calculate two figures: 1) the posterior (I think its called?) probability based on their record, e.g. 27/41 for Tom vs Dick and 12/36 for Dick vs Harry 2) the estimated probability based on ELO, e.g. http://tournaments.tantrix.co.uk/ratings/simple.shtml I perform a chi-squared test on the two 'series' to determine if they have the same mean. If they do, then no head to head effect, if they don't then there is a head to head effect Am I moving towards something here or barking up the wrong tree (still/again !!) . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
