Eliminating Non-Contenders? Ideas? Math?
 

I'm very curious to see how various people\methods go about "eliminating the non-contenders". Every handicapping book i read says this is the first thing to do, but I can't find any good statistics to back up the "easy eliminations" they recommend.

So I built this little number to try out a few ideas I have, but I don't have that many. Anyone have some ideas they've always wanted to test? I'll be glad to share the results here of every idea, or send to you directly if you prefer.

I have a database of 898 Fast Dirt races from Aquaduct's 2004 season.

I'll post a few of my tests here over the next few days...

-Phil O'Donnell

Test Name:
"Eliminate the horse with the lowest BRIS Power Rating if the last race was at a lower class level than this race"
Result:
432 Horses eliminated in 432 Races
6 Eliminations per Hundred finished 1st (94% Accurracy)

Good post, but I suggest factoring in ROI into your tests. I agree about some of these non-elim rules published. Some of my tests have shown these elim tests could actually be wokred into longshot methods. Low hit rates but boxcar mutuels.

Eliminations
 

This opinion will go againest everything you read on handicapping,but a quick and dirty way to elimnate horses is to look at the morning line if its over 8/1 on a horse its chances of winning are usually 50% less than what the M/L indicates .After you play a track for a while you will get a feel for accuracy of the odds maker.High M/L odds horses do win of course but its usually a shipper or a long lay off horse .The horses i like to watch for are M/L horses that are 5/1 or less but are going off at much higher odds .I take a close look at these .Sometimes you will find a good overlay.
FWIW

Test:
Eliminate all horses with morning line odds greated than 8/1
Result:
Eliminated 2456 Horses in 797 Races
11 Eliminations per 100 finished at least 1st (89% accuracy)
31 Eliminations per 100 finished at least 2nd (69% accuracy)
57 Eliminations per 100 finished at least 3rd (43% accuracy)
93 Eliminations per 100 finished at least 4th (7% accuracy)

How about eliminate all horses in the race that are not one of the first four favorites in the wagering when the horses leave the paddock.
My late father used this method successfully for many years in So. Calif.
He would handicap the horses, look at the horses in the paddock, live, circle horses who looked good, then check the tote board when they left the paddock. He would usually box contenders in exactas unless he was using the first three favorites....then he would pass the race.
He seemed to always have winning meets.

1. When the morning line favorite is 3-1 or higher eliminate this horse.

2. When the morning line favorite is 3-1 or higher eliminate this horse and the next closest horse in odds. The second favorite.

All races since April 2005

# races - 61,536
#>8-1 ML - 193,116
# wins - 8213 4% of horses, 13 percent of races

Test:
Eliminate all favorites with morning line odds greated than 3/1
Result:
Eliminated 61 Horses in 61 Races
15 Eliminations per 100 finished at least 1st (85% accuracy)
36 Eliminations per 100 finished at least 2nd (64% accuracy)
52 Eliminations per 100 finished at least 3rd (48% accuracy)
64 Eliminations per 100 finished at least 4th (36% accuracy)

This is not encompassed by your database but one of the finest, if not THE finest throwouts in all of racing is:

Mountaineer morning odds 30/1 - all races since jan 1, 2005: 2 wins out of 942. Those 2 winners went off at odds of 43.1 and 61.2. No way to slice or dice this one - throw em out. Yee Haw!

Ron Tiller
HDW

I had 'em BOTH! :rolleyes::liar:

Well, I don't have the odds when the horses leave the paddock, but here's it based on the final odds:

3222 Horses eliminated in 854 races
0.17, 0.43, 0.78, 1.24 (83%, 57%, 22%, 0%)

Sounds good to me. Just about what I thought. High priced morning line favorites win nowhere near 33%.

I'd like to see the same test done with a larger data base. I think the results would be about the same.

Just so everyone knows, I have the pps from every one of those races, so your eliminations can be more detailed than just odds.

Examples:

• Need-to-lead horses who did well in thier last one or two races, but won't get the lead today. (Quinn, 2003)
• Following a claim, a layoff of longer than 30 days followed by a drop in class below the claiming price (Quinn, 2003)
• The last running line shows a win, but the horse failed to return for six weeks, except graded stakes horses who may be shopping. (Quinn, 2003)

Try this:
 

Eliminate all dirt horses who have had more that 1 layoff of 60 days or longer showing on the PP's. (Turfers may lay off for the wintewr anyway).

Except for the occasional sprinter who might take the lead, horses four and older competing at new distances are best eliminated (Quinn 2003)

367 horses in 196 races
0.23 0.44 0.64 0.87