Using the Brisnet Prime Power Rating to Ferret Out False Favorites

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Derek Simon

November 14th, 2014

On my latest podcast, I discussed the benefits of finding a “false favorite” in a race — a horse whose morning line status isn’t justified by its past performances. However, I freely admitted that taking advantage of such a scenario is easier said than done.

While it’s clear that tossing a horse commanding a large portion of the pari-mutuel pot makes sense, to make a few dollars, a handicapper must also find something he/she likes in the race… and therein lies the rub.

Well, fret not, my fine-feathered friends (I like to picture my readers wearing boas and sipping tea), for I have done just that.

As many handicappers already know, the Brisnet Prime Power rating does a great job of assessing equine talent. In fact, in a recent study of over 11,000 races, I found that horses possessing the top Prime Power rating performed better than morning line favorites in terms of winning rate and ROI and almost as well as morning line favorites in terms of determining which horse or horses the public would ultimately bet down.


Number: 10,584
Winners: 3,576
Win Rate: 33.8%
ROI: -14.68%
Times Favored: 63.7%


Number: 11,432
Winners: 3,819
Win Rate: 33.4%
ROI: -17.70%
Times Favored: 66.2%

Of course, what we’re looking for is a bit different — mainly, a morning line favorite (or a post-time favorite for that matter) with a low Prime Power rating, suggesting that the horse in question is vulnerable or weak. If we can find such horses and they do, indeed, underperform, we’ll be in business.

Well thanks to the miracle of computer databases, along with healthy shots of NoDoz and Red Bull (sugar-free — gotta watch those carbs), I found a subset of morning line favorites that met my low expectations.

Rather than focus on a specific Prime Power number, I simply insisted that the morning line choice have a rating ranked sixth or worse. This not only guaranteed a lowly relative Prime Power number, it also assured a bigger field, which I hoped would make it easier to capitalize on the faulty favorite down the road.


Morning Line Favorite

Number: 408
Winners: 72
Win Rate: 17.6%
ROI: -32.54%
Times Favored: 32.4%

Actual Race Favorite

Number: 342
Winners: 93
Win Rate: 27.2%
ROI: -21.29%
Times Favored: 100.0%

As you can see, more often than not, the low Prime Power rating pointed to a poor morning line rather than a poor favorite. However, given that most morning line favorites are at least among the top betting choices, the stats are still illuminating.

Now, as I opined on my podcast, it is my belief that the best way to attack a race with a vulnerable favorite is to use the same criteria that pinpointed said favorite to find other, more viable contenders. In this case, since we are employing the Prime Power rating to find our fake favorites, we’ll also utilize it to ferret out our alternative play(s).

After some tinkering, I came up with the following:

In races with a vulnerable morning line or post-time favorite, look for a horse with a Brisnet Prime Power rating (of 125 or greater) that is ranked among the top two in the field.

Below are the results:

Vulnerable Morning Line Favorite

Races (Plays): 78 (117)
Winners: 27
Race Win Rate: 34.6%
Total ROI: +21.75%

Vulnerable Post-Time Favorite

Races (Plays): 69 (104)
Winners: 18
Race Win Rate: 26.1%
Total ROI: +8.70%

Not surprisingly, playing against a (perceived) poor morning line favorite produced much better results than playing against a (perceived) actual favorite — the crowd’s collective judgment is tough to beat — but both techniques  were profitable.

Whether such a simplistic approach can stay profitable remains to be seen, but I think there’s a lot of merit to the underlying concept.