I'm looking for the wisdom of experience on the question of how we select what races to punt on and how we determine which races to avoid. Obviously, some races are tougher to find a winner in than others. I have used the rough n ready guide of no more than 14 runners to hone in on the easier races but I'm interested in other methods. (And then there's the problem that the easier the race the less the dividends...)

Here's a thought on rating races by degree of difficulty:

Refer to the Zip form scores in the Sportsman Chartform.What is the difference between the top Zip and the bottom Zip?

Eg. If the top scored Zip in the race = 56 and the weakest roughie is rated as a Zip = 48, the difference = 8.

Now divide that number into the number of runners.

If the Zip diff. = 8 and there are 16 runners the result = 2.0.

Anything higher than two is a bad race to pick (or set your own cut-off)

I figure that if the Zip form analysts and all their computer power can't tell 'em apart, how can I?

Some examples from Sat. 8th June 2002.

Race 2 Eagle Farm.

Top zip = 55
Bottom zip = 48
Diff = 7
Runners = 20
7/20 = 2.85

NO BET

Race 3 Eagle Farm

Top zip = 58
Bottom Zip = 49
Diff = 9
Runners = 16
9/16 = 1.77

WORTH A BET

Any thoughts or other methods?

Cheers