Most vulnerable types of races where favorite is consistently beaten?

[acorn54]

my two cents. i have been using a data base since 2004, and in my observations, the scenario's where the favorites fair poorly are pretty cut and dried. it is simply the larger the race field the more likely the most favored horse in the race is not going to find the winner's circle. the reason is self- evident...the more horses that have to be beat, the more difficult the feat is.

[JerryBoyle]

Originally Posted by acorn54

my two cents. i have been using a data base since 2004, and in my observations, the scenario's where the favorites fair poorly are pretty cut and dried. it is simply the larger the race field the more likely the most favored horse in the race is not going to find the winner's circle. the reason is self- evident...the more horses that have to be beat, the more difficult the feat is.

Out of curiosity, I just queried this from 20180101 to 20180714 for NA horse racing covering 23918 races. Below is the final, track adjusted probability for all winners. Your 2 cents is worth more than that

                      mean       min       max       std  size
number_of_horses
2                 0.661510  0.484529  0.754545  0.153337     3
3                 0.426682  0.086458  0.780952  0.155409    37
4                 0.369483  0.030826  0.810000  0.165348   350
5                 0.314850  0.016129  0.805429  0.160916  1985
6                 0.282615  0.020329  0.790476  0.157341  4757
7                 0.255267  0.010931  0.790476  0.148384  5087
8                 0.232237  0.009336  0.754545  0.140588  4462
9                 0.220214  0.010553  0.754545  0.139242  3306
10                0.200269  0.009253  0.771429  0.129277  2669
11                0.197563  0.009529  0.687500  0.129179   772
12                0.180528  0.009318  0.691667  0.115152   506
13                0.136155  0.012353  0.415000  0.105092    22
14                0.103976  0.010506  0.323077  0.079885    21
16                0.265781  0.265781  0.265781       NaN     1
20                0.211538  0.211538  0.211538       NaN     1

Edit: Actually, this doesn't really help. Little too early in the morning for me...

[AndyC]

Originally Posted by acorn54

my two cents. i have been using a data base since 2004, and in my observations, the scenario's where the favorites fair poorly are pretty cut and dried. it is simply the larger the race field the more likely the most favored horse in the race is not going to find the winner's circle. the reason is self- evident...the more horses that have to be beat, the more difficult the feat is.

Isn't it simply the higher the odds of the favorite the worse they perform? I doubt that even money favorites perform worse in a large field than they would in a small field.

[cj]

Originally Posted by AndyC

Isn't it simply the higher the odds of the favorite the worse they perform? I doubt that even money favorites perform worse in a large field than they would in a small field.

This would be correct. Keep in mind that in the few match races even money horses are not the favorites. I used all horse that went off at 0.90 or 1.00. I accidentally left out horses at 0.95 but I'm not going to run this over again. There weren't enough of them to make a difference.

[CincyHorseplayer]

Originally Posted by GMB@BP

Not sure on your stat, i have 36% win percentage in 618 races with a horse that was at 0-2/1 with a 0.82 ROI. I would need another month of data to get 1000 races though but doubt it changes by more than a percentage.

It's only races I have personally handicapped that are in the base. I'm precisely certain of that number or I wouldn't put such an emphasis on betting grass! Maybe some players start with an "All" button to analyze races by surface in a generic database(and by that I mean the whole big globule of actual reality) but it's better when they are races you know by having done the work on them. I can add that the number 13% is based only off my graded contenders. But the actual sub 2-1 group doesn't make it to 20%.

[Tom]

Looking at the Oceanside today at Dmr....BRIS shows this type of race - 3yo Stake 75000-300000 Turf 8-9 furlong, favorites winning only 20% out of 15 such races. Median payoff of $15.20.

Race to be looking for a price?