   Ranking system problem
  I'm sure this something tackled by thousands before me, but I'm looking for a ranking system.  I can find plenty of player vs. player ranking systems on the net, but this is pure win/loss based on picks.  So, I'd like to rank based on win/loss record, number of games participated in, and maybe factor in total number of games possible.  So, 5-0 would not beat 30-10.  A person that has picked that many winners should rank higher than someone who has gotten lucky and picked 5 winners.  Anyone have a good algorithm or points system for a win/loss ranking such as this?   
  Have you considered simply stealing the one that is used for chess? [EDIT] Decided to save you the trouble of looking it up. Only thing is it's only appropriate for 1v1 type games. You might be able to adapt it or take the basic ideas though.   ;  Yeah, I've looked at several chess systems, and football ranking systems.  Problem is, a main factor is the strength of the opponent.  In my game, no one plays anyone else.  They simply pick winners, and get a win if their pick wins.   ;  The simplest likely-to-work-reasonably-well solution I can think of (justifying it involves, of course, a lot of statistical handwaving) is to simply subtract a factor proportional to the square root of total games:Score = (wins / (wins + losses)) - K(sqrt(wins + losses))   ;  This is a reply I got on another board:Quote:I think we are thinking about this wrong.  Some how we need to give a win/loss some sort of weighting as i had based on total number of games playedLike if you have played 50 games a win is worth 1 and a loss is worth .5 but if u have 100 games then a win is worth .85 and a loss is .45 or some sort.  then we figure out that sum.  An equation for that is like$factor_w = 100;$factor_l = 85;$games = 50;$wins = 25;$losses = 25;$total = ($wins/($factor_w/$games))-($losses/($factor_l/$games));So this generates a value that will be put in to $a*exp($k*$total);  Where $k is to keep the values realistic and $a is to create more significance to the outputted value.  However this results in an issue because $total could be <0 which means if you have more losses than wins you are going to be really low down.  Somehow it has to be exponential, but somehow it has to take into account games and wins vs loss ratio.  we could just use that outputted $wins/$games which si your wining percentage.  then take exp($wins/$games)  which takes into account losses.  You seem to be worried about combining all three leagues together, but that isn't nessecary until after you get the inital values create.  Then its easy.  but the problem at hand is creating an equation where 25-0 is equal to 75-4 but less than 101-7 for example.