The Wringer of Reality

Dosage “gurus” are not very forthright. They rarely come right out and say what they mean. You have to do a lot of reading between the lines. Perhaps this has resulted in some misinterpretations, but that is to be expected if you do not say what you mean and mean what you say.

The heart of dosage theory is that a “balanced” pedigree is better than an “unbalanced” pedigree. Any by “balanced” they mean a pedigree that has a good mixture of speed and stamina (not all speed or all stamina).

That all sounds pretty reasonable. Indeed, it is pretty reasonable. As usual though, the problems arise with their definitions.

A pedigree with a dosage index (DI) of 1.00 and/or a center of distribution (CD) of 0.00 is considered to be “balanced” perfectly, at least theoretically. The DI possibilities range from 0.00 to infinity. The CD possibilities range from –2.00 to +2.00.

Most people who follow this stuff have the impression (rightly or wrongly) that a pedigree with a DI of 1.00 and/or a CD of 0.00 is “better” than a pedigree with numbers above or below those ideal numbers. This is the nexus of dosage as a breeding theory. The clear implication is that breeding a better racehorse involves creating pedigrees as close as possible to those ideal numbers of a DI of 1.00 and/or a CD of 0.00.

In reality the vast majority of all racehorses have DIs higher than 1.00 and/or CDs higher than 0.00. In fact it is pretty difficult to find racehorses with a DI of 1.00 (or lower) and/or a CD of 0.00 (or lower).

CD is a more precise measure than DI. Therefore, I thought it might be interesting to identify all sales foals of 2003-2007 who have a CD of 0.00 (zero) and see just exactly what their results were in terms of price and performance.

The five stakes winners listed below all have a CD of 0.00. Listed for each is its name, its pedigree, its sales info, its dosage profile (DP), and its number of Performance Points. They are listed by decreasing number of Performance Points, from Silver Timber with 1,875 to Another Kris with 189.

Silver Timber (Prime Timber—River Princess, Alwuhush), 05T110,000, 2-0-10-0-2, 1,875.

Sky Mom (Maria’s Mon—Swiftly Classic, Sky Classic), 06Y27,000, 2-2-10-2-2, 989.

Carminooch (Tomorrows Cat—Open Flap, Carr de Naskra), 1-2-8-2-1, 03Y5,000, 682.

Salty’s Glider (Honor Glide—Tooosalty, Salt Lake), 04W37,000, 3-4-6-0-5, 275.

Another Kris (Kissin Kris—Super Princess, Super May), 04W5,000, 0-1-8-1-0, 189.

If only 100 or so foals in the entire group had a CD of 0.00, this would be a pretty good result. If 500 or so foals in the entire group had a CD of 0.00, this would NOT be a good result.

I will list all the foals with a CD of 0.00 in a separate post. Including these five stakes winners, there were 417 such foals.

Those 417 foals were not exactly popular at the sales. They sold for a gross of $9,553,862, an average of $22,911 (well below the overall average of $54, 140), a maverage of 106.07 (well below the overall maverage of 163.11), and a Price Index of 0.65 (1.00 being average by definition).

The market obviously did not think very highly of these 417 pedigrees. And they were correct to do so. Five stakes winners from 417 foals is 1.20%, well below the overall figure of 3.41%. Those five stakes winners did average 802 Performance Points apiece, well above the overall average of 617.

So they were pretty good stakes winners. But their quality was not nearly enough to overcome their surfeit of quantity. Taking both into account, these 417 foals had a PPI (result) of 0.46, which does not compare favorably with their Price Index of 0.65.

So these 417 foals sold for prices about 35% below average and produced results about 54% below average. They sold for low prices and still managed to underperform those low prices.

This is what happens when theory meets reality. The theory that a pedigree with a CD of 0.00 is a “good” and perfectly “balanced” pedigree is thoroughly rejected.

I would not be the least bit surprised if the highest prices and/or best results were achieved by nags with DIs and/or CDs closest to the median for the population. That is just common sense. The middle of populations frequently has better results than the extreme low or high ends of populations. And a DI of 1.00 and/or a CD of 0.00 is on the extreme low end of Thoroughbred populations.

Dosage postulated a theory and then assumed its theory to be reality (or even worse, dogma) without even testing it on the overall population. The scientific method is to test theories by running them through the wringer of reality.

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One Response to The Wringer of Reality

  1. Jane Heidelberg says:

    To my thinking, if dosage has any value at all and the stats aren’t jiggered to fit preconceived notions, the value comes in categorizing the length predispositions of sires and their progeny.

    It seems to be a well established concept that regular infusions of speed are necessary to keep lines from becoming plodders. Whether that is still true today with all the Nearctic around is questionable, but it has definitely been a breeding principle for many decades. Speed to speed would seem to lose distance. In her book on Northern Dancer, Avalyn Hunter says that Tesio was a proponent of speed on the bottom and stamina on top. It appears that most breeders prefer the opposite.

    So a method to determine which sires produce speed and which produce distance would seem to be necessary. Dosage is just one of the many ways that stats are used to create categories. And that, to me at least, is its only value.

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