Hi Moe,
If winning at the races was easy, everyone would be doing it..
In the table I posted, the first column contains .50 which is 1/$2.00 payoff, if you were to then add all the .5's or $2.00 starters in every race for a week the total might be say 10. The expectation would be you'd expect there would be 10 actual winners.

So now in the 2nd column i have a percentage figure of say 90% that means there were only 9 winners if you applied it to the above example, when you do this, you can then see how efficent punters are in that range.

You then can use it to see how efficent say a jockey is if you totalled all his runners probs you then could compare his actual to expected...an so on..its very simple but very powerful an its unlimited in its application...