It’s easier to get lucky when…

[formula_2002]

It’s easier to get lucky when…

I took my 259000 horse data base and broke it up into sets of 100 and calculated the actual wins vs. the expected wins (expected wins=1/(odds+1)
2590 sets returned an a/e ratio (your roi when the wager is based on the odds book percentage) of .81 that’s the result of a bet on all horses.
In the 2590 sets, there was never a time when the roi turned positive.

When a book % bet was limited to the odds range >=.05 to <1, the roi was .85 and never did the roi turn positive in the 66 sets of 100.

Book % bet when odds >=1, <2…roi=.83 and 5% of the 196 sets were positive
Book % bet when odds>=2, <3…roi=.84 and 10% of the 234 sets were positive
Book % bet when odds >=3, <4...roi=.79 and 14% of the 210 sets were positive
Book % bet when odds >=4, <10...roi=.82 and 15% of the 974 sets were positive
Book % bet when odds>=10, <20...roi=.80 and 29% of the 500 sets were positive
Book % bet when odds>=20, <50...roi =.71 and 19% of the 449 sets were positive

[formula_2002]

I wonder if all of that could make a case for there being a "natural overlay" by the percentages indicated for those various odds ranges.
Natures natural overlays!! :)

[CBedo]

About three or four years ago, I did a similar study. The studies I did (larger samples, smaller number of total sets) showed similar results, with the exception that thr ROIs I calculated started falling towards the lower end of the range sooner than your sets did. My numbers started to drop quickly after the odds exceeded 9-1. The numbers of positive sets were pretty similar, but never reached anything much over 20%.

So for me, as the average ROI went down, the standard deviation went up dramatically, which seemed logical when you consider what your losing streaks can look like as the average odds of your wagers move up (win or exotic).

[formula_2002]

I just ran the odds range >=10 and <20 (which by the way, is only a 4% win probability difference)

@ 50 plays per set, 28% of the sets were profitable
@ 200 plays per set, 28% of the sets were profitable.
all the same as the 100 plays per set.

So in my book I can throw darts at all the >=10, <20-1 and have a 28% chance of hitting one that is under valued..
But that doesn't put any more chicken into my soupe.

I can get luckier at roulette!! :cool:

[formula_2002]

when the bris prime fig =1 the is a 60% of showing a profit in 8 sets of 50 plays in the range >=10, <20