I like to apply stats to my ratings. I am looking at ways of correcting for the number of starts a horse has had be it too small or too large.

I would like to get the mean and standard deviation of number of starts for a larger sample than I have at present if someone can help.

I have found this for a recent 7 weeks of racing in Brisbane and found the mean to be 21 and the standard deviation to be 14.

This is just a ball park stat because of my small sample size but it suggests that some adjustment should be made for horses that have had fewer than 7 starts (mean-one stdev) and for those with more than 35 starts (mean+one stdev).

I would appreciate any ideas and better data on this.

gunny72