R/s By Ppo

[George]

Told Neil would try to run an analysis of CD for runstyle by post position. My results were based on such small amounts of data they were not very smooth. I did run the same analysis for all tracks from Feb 2001 thru May 18th. Will try to attach for perusal.

The spreadsheet lists percent wins for the total starts for each runstyle by post group 1-3, 4-6, 7-9, 10-12. Ran for dirt sprint, dirt route, and turf route.

The analysis awakened me to a fact that Bruce alluded to and that is jockey R/S percents need to be adjusted to IV'S BY rs/post. A jockey riding 25% winners on S routes is doing far better than a jockey riding 25% on E routes.

Gary Stevens since Feb has done 40% on P route from post 10 or greater. Spreadsheet indicates that 10.2% is norm. Gary's IV is 3.92!!! FOR THAT CATEGORY!!
Point Given looked a lot better as a bet if one knew that.

[Neil]

Thanks, George. I'll look at this over the next few days, and we can discuss at Las Vegas. Appreciate the effort.

Neil

[Glen]

Thanks George. Good stuff. I had run some test similiar to what you just did last month and it really opened my eyes to false favorites and other myths. Mucho bueno!

[hurrikane]

you have seen me post about the trn/jk db...curious does anyone have stats on just the win% for rs.. Also..george..can you send me the formula you ust AP and IV. thanks

[George]

Not sure what you mean on AP but think you meant AE or actual/expected ratio. Here is AE formula.


Expected Win% = (1 / (Odds-to-1 + 1)) * (1 - Track Take)

If we imperfectly estimate the track take as 18 cents on the dollar or .18, then the calculation
goes like this:

Expected Win% = (1 / (Odds-to-1 + 1)) * (1 - Track Take)
Expected Win% = (1 / (4.0 + 1)) * (1 - .18)
Expected Win% = .2 * .82
Expected Win% = .164

We expect horses with average odds of 4.0-to-1 to win about 16.4% of the time. Plugging this into our A/E calculation, we get:

A/E Ratio = Actual Win% / Expected Win%
A/E Ratio = 17.0 / 16.4
A/E Ratio = 1.03
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Impact value can be baselined to anything you want. On the jky/rs db I am currently using win percent by rs by distance/surface as base.
If dirt sprint rs P wins 16% and jockey wins 32% on dirt sprint rs P then IV is 32/16 = 2.00
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Win% by rs can be gotten from modeler for each track and averaged by all tracks. Or simply run a query of all tracks on your db for rs.

Hope this is more clear than it looks:)

[hurrikane]

Thanks George...have you found any advantage between iv and ae

[George]

Have found the AE to be very useful in looking at potential new spot plays. If the AE is below 1.90 I immediately know it won't be useful. No amount of tuning will improve it the return.

Have added IV to my jky/rs a few days ago and am just beginning to track it Looks hopeful so far.