"Sid" <[EMAIL PROTECTED]> wrote in news:[EMAIL PROTECTED]:
> Hi, > > We can look at the performance figures for any sport, team or player. > > What I want to do is produce an weighted average for this figure. > Older figures should have a lower weighting, scaled by two variables - > both the number of games ago this performance was achieved AND the > time since that performance. > > For example a figure of 65 achieved 3 games and 28 days ago would be > worth less than a figure of 65 achieved 3 games and 16 days ago, which > in turn would be worth less than a figure of 65 achieved 1 game and 16 > days ago. > > Any ideas, formulas, references would be appreciated. The first thought that comes to mind is that you'd need to mean-center the performance figures before weighting them. I assume the point of the weighting is that knowledge of older performances should have less effect on how a player is rated than knowledge of new performances, rather than that older performances should be regarded as *worse* than new performances, which is what you'd get if you didn't mean-center. . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
