Give a brief insight into the method of ranking cricketing players.
Cricket players are ranked using a math technique called ‘Exponential Weighting’. It is sometimes
referred to as "moving average." To figure a cricket player's ranking using exponential weighting
(W), add the total scores (S) in a number of games and then divide the total scores by a decay factor
(K). The formula is S/K=W and the decay factor places more value on recent scores and less value
on older games. If the decay factor is 10 percent, then game is valued at 0.10 less than the following
game. For example, game five is valued at one, whereas game one is valued at 0.6. Figure the
weighted average by adding up all the values for W, then divide the number by K. The formula is
A=W/K, and the official rankings use a decay factor of 4 percent.
What can you infer about the ranking of a player who performed better in later games.
Do you think this is an effective method of ranking the players? Explain with reasons.
If we elliminate decay factor
then we have relation
where A - weight average and W-exponential weighting
S- total score in n games.
So in ranking , n the number of the game player played game is not contibuting at all.
Every time we concern about average , which is it self in conclisive.
S is assume proportional to `W^2` ,which not seems true. Thus ranking improved if player perform good in few games. Nothing conclusive about consistency and stability of the performance.
Thus ranking system is in appropriate.