Tuesday, April 27, 2010

Daily Kentucky Derby Hype Meme: Dosage

It's a slow week so far in Louisville, with the big stories being Eskendereya's scratch, which we covered yesterday, and Joe Torre's ownership of Homeboykris and involvement in racing. The latter is almost half the product of the Dodgers being in New York and rained out yesterday. We thought we were going to have nothing to kvetch about today, and then an old friend resurfaced: Dosage.

We thought Dosage was dead and buried, until we saw this cheatsheet given to the masses in the Louisville Courier-Journal, the main paper of Louisville and the go-to source for local Derby coverage. Suffice to say tens of thousands of people will be reading this chart and others like it, and quite possibly relying on it. On its face it has some good information: the horses' connections, breeding, race record, last race finish and best speed figures. But in the penultimate column, it also gives every horse's Dosage figure. Arrrrgh.

A horse's Dosage Index is calculated by a fairly complicated process, illustrated by the 12-part slide show here. In short, Dosage puts all sires into one of five categories based on how far it thinks their progeny want to run. Points are assigned for all sires in a horse's lineage, going back four generations, with the most recent generation's points counting the most. By adding up the points, multiplying them by a constant, and then applying Euler's Formula, we get a horse's Dosage.

A series of articles in the Daily Racing Form in the early 80's posited that if a horse had a Dosage above 4.00, he could safely be eliminated from the Derby on breeding alone. A fine theory, which held true for a while. And then:
  • Strike the Gold won the 1991 Derby with a 9.00 Dosage, despite being sired by Alydar, one of the best 3yos ever.
  • Real Quiet and Charismatic won the Derby in back to back years with Dosages over 4.00.
  • Giacomo and Mine That Bird pulled off big upsets with Dosages over 4.00, neither of which made any sense, given they were sired by Travers winners.
What this means is that Dosage has a 75% hit rate--3 in 4 winners of the Derby will have a Dosage below 4.00. Here's the greater problem: almost all horses that run in the Derby qualify based on Dosage. Taking this year's possible entrants (excluding Rule, who's not running), this would knock out Mission Impazible, Jackson Bend and Conveyance, leaving you with 17 horses that qualify based on Dosage. Thank you. Moreover, the fact that a horse has a 1.00 Dosage versus a 3.00 Dosage is patently irrelevant in Derby success; all that matters, under the old theory, is whether he's under a 4.00.

We would have less of a problem with a paper that doesn't really have a racing beat mentioning Dosage, because old habit die hard. But the Courier-Journal should know better, horse racing and bat making are the only two games in town. This isn't just giving out bad information, this is giving out misleading information that's been disproven time and time again. We'll therefore give this a solid 7, and advise everyone to avoid Dosage like the plague.

1 comment:

Teddy said...

The only dosage number I care about is expressed in milligrams of Winstrol.