Exception Proves the Rule
Just to clear up two questions that might arise from my last post on Galileo’s conditions of possible effectiveness (let’s call it CPE) with mares that have Sharpen Up in their ancestries.
First, that post established that Galileo’s probability of siring superior runners out of mares that descend from Sharpen Up through either Kris or Diesis is at least .28. Doubly Sure, the dam of Kris and Diesis, seems to be the key factor, especially considering that Cape Blanco (G1) is out of a daughter of Doubly Sure sired by Presidium, by General Assembly rather than Sharpen Up. That leaves open the question how well Galileo might handle mares in descent of Doubly Sure through her daughters, and I would have mentioned it except that Galileo has had only one such mare.
Second, I mentioned that Galileo had sired a superior runner out of only one mare of the 29 that descended in some way from Sharpen Up, but not through Kris or Diesis. So, the problem is, if descent through Kris or Diesis is a CPE governing Galileo’s relation to Sharpen Up, how can 16.5-f Marathon S. (Sandown, 2010) winner King of Wands (Galileo ex Maid to Treasure, by Rainbow Quest and an image in the Tarot, I believe) be explained? His third dam is by Sharpen Up.
The answer is that, even if a mare fails to fulfill a CPE relating to one of her ancestors, she may still fulfill other CPEs that control a sire’s potential. Now, Galileo doesn’t have a great strike rate with Rainbow Quest–only 4/24–and his record with Blushing Groom is 9/75. What is more likely decisive in the ancestry of King of Wands’ dam is her broodmare sire Indian Ridge, with which Galileo has a strike rate of 4/11. Moreover, his overall record with Indian Ridge’s sire Ahonoora is 6/18. That’s a superior-runner probability of at least .33.
It’s clear, then, that Galileo’s CPE relating to Indian Ridge and Ahonoora, whatever it might be, is far less stringent than his CPE relating to Sharpen Up. Furthermore, because of Sharpen Up’s generational distance in this case, his normal negative effect on foals by Galileo (when not descending through Kris or Diesis) is much less likely to be expressed than the highly favorable effect associated with Indian Ridge.
Discovering the conditions of possible effectiveness is a critical function of pedigree interpretation, and, while it can only yield probabilities comparable to those of, say, short-term weather forecasts, those probabilities are a lot more reliable than reading tea leaves, questioning the Ouija, or trusting in the make-believe deficit reduction in Paul Ryan’s budget proposal.
UPDATE: In the Tarot, the King of Wands denotes the ability to persevere toward a goal, overcoming all obstacles by exceptional means. Seems appropriately named.
Posted by Roger Lyons on Monday, April 18, 2011 at 8:18 am.
The Possible and the Probable
by Roger Lyons
In previous posts I’ve noted that breeding methods are subject to conditions of possible effectiveness. That is to say, any given topic of pedigree discussion–a nick, a method of inbreeding, any combination of one ancestor with another–can yield a stakes winner if certain conditions are met by the specific cross. By definition, a cross that does not meet any conditions of possible effectiveness has virtually no chance of yielding superior performance. We can’t always know whether or not a cross meets conditions of possible effectiveness, but, given what is at stake, any evidence of such conditions is worth considering.
I would go so far as to submit that the conditions of possible effectiveness are crucial to determining the probability of superior performance from a cross. Here’s a case in point.
Last year I mentioned the nick between Galileo and the sons of Doubly Sure–Kris (by Sharpen Up), Diesis (by Sharpen Up), and Presidium (by General Assembly). At that time, 25 mares with one of those three sires in their ancestries had produced foals by Galileo, and six different crosses had yielded superior runners, including three G1 winners (Sixties Icon, Lush Lashes, and Cape Blanco) and New Zealand, which ran second in the Irish St. Leger (G1). Since then, Gallic Star, whose third dam is by Kris, won the listed Silver Tankard S. in England, bringing the total number of superior runners to seven.
Thus, assuming a mare of similar quality in some descent of Kris, Diesis, or Presidium–all out of the mare Doubly Sure–the probability that she can produce a Galileo foal capable of superior performance is at least .28, the probability of a G1 winner at least .12. Don’t get caught up in the fact that Kris and Diesis are by Sharpen Up. Galileo’s record of 7/53 with Sharpen Up suggests only a .13 probability of superior performance (not adjusted for the conditions of possible effectiveness).
But, we know from the numbers that the presence of a son of Doubly Sure in the ancestry of a mare is a condition of possible effectiveness for offspring of Galileo. That condition is met by 24 of the 53 mares with Sharpen Up in their ancestries, and six of those seven dams of superior runners met that condition. This means that Galileo’s strike rate with mares in descent of Sharpen Up, but not through a son of Doubly Sure, was only 1/29, with a probability of only .034 of yielding a superior runner. In other words, those cases do not meet Galileo’s conditions of possible effectiveness with Sharpen Up.
It’s perfectly reasonable to think of the probability of success as a frequency of superior performance from opportunity, but that reasoning goes wrong in thinking of opportunity as nothing more than the number of times a cross has been tried. It might be fair to say that the number of times a cross has been tried constitutes its nominal opportunity, but the real opportunity is defined by the cases that actually meet conditions of possible effectiveness. An “opportunity” that has virtually no chance of success is an opportunity you can do without, especially when trying to pin down a true probability of superior performance.
Posted by Roger Lyons on Thursday, April 14, 2011 at 6:43 am.
Native Dancer at the Vanishing Point
by Roger Lyons
Native Dancer has reached a genetic vanishing point in the sense that his influence is so pervasive that his contribution can no longer be contrasted in any significant way with the mainstream of the population. This is evident from the table accompanying my last post, which shows that in no instance do the strike rates of US stallions with mares in some descent of Native Dancer exceed their overall records. That is, no “contemporary” US stallion has a statistically measurable preference for mares in descent of Native Dancer. Keep in mind, though, that it’s because the broodmare population is so largely defined by Native Dancer. It’s like the air they breathe.
Moreover, only two stallions–Diesis and Dixieland Band–(that the table rather loosely defines as contemporary) fall below their normal strike rates when crossed with mares in some descent of Native Dancer, and they are both deceased. They were bred quite differently from one another with respect to Native Dancer–Diesis, by Sharpen Up, by Atan, by Native Dancer, and Dixieland Band, by Northern Dancer, out of Natalma, by Native Dancer.
Reasons can no doubt be given for why they had trouble with mares in descent of Native Dancer, but the fact that they did so has always had more practical import than the reasons why. More interesting here is that their aversion to mares in descent of Native Dancer and their shared birth year of 1980 renders their stud records especially useful as measures of the proliferation of Native Dancer’s influence.
Consider what it could mean that both of these stallions had significantly higher strike rates with mares born prior to 1985 than with mares born after that year.
Dixieland Band got superior runners from 50 of 435 individual mares born prior to 1985, for 11.5%; but, of the 644 mares born after 1984, 51 produced superior runners by him, for only 7.9%. Furthermore, only 23 of the 396 mares born after 1989 produced superior runners by him, for only 5.8%. As Native Dancer’s influence spread throughout the later population cohorts, Dixieland Band’s strike rate with those mares declined. Of the 219 mares with Northern Dancer in their ancestries, only 10 produced a superior runner, and he was barely in range of his average with mares in descent of Mr. Prospector.
Diesis’ stud record reflects the same broad pattern. While 48 of 343 mares born prior to 1985 produced superior runners by him, or 14%, only 28 of 453 (6.2%) born after 1984 did so. Of the 277 mares born after 1989, only 10 (3.6%) produced superior runners by him. Diesis got a superior runner from only one of 64 mares with Mr. Prospector in their ancestries, and he was barely in range of his average with mares in descent of Northern Dancer.
With each successive broodmare population cohort, in which crosses of Northern Dancer and Mr. Prospector assured a rapid accumulation of Native Dancer influence, the strike rates of Dixieland Band and Diesis declined. It seems warrantable to conclude that Native Dancer’s proliferation in the broodmare population had a more profound effect on their stud records than could possibly be attributed to a decline in viability due to increasing age.
Posted by Roger Lyons on Tuesday, February 22, 2011 at 6:48 am.
Galileo and the Sons of Doubly Sure
by Roger Lyons
The cross that yielded Cape Blanco (Galileo-Laurel Delight, by Presidium, by General Assembly), recent winner of the Dante S. at York, is formally an A nick based on the Sadler’s Wells-General Assembly cross. Galileo may never get enough opportunity with Presidium mares to confirm a simple sire-broodmare sire nick in the conventional way, but this is not a conventional nick.
The fact is that Galileo has done a lot better with mares whose ancestries contain Presidium’s dam, Doubly Sure, than he’s done with Secretariat-line mares. Seven of his 27 mates that had Doubly Sure in their ancestries produced superior runners by him, including Cape Blanco’s dam.
Now, Doubly Sure is also the dam of Kris and Diesis, both by Sharpen Up, and they both have simple A+ nicks with Galileo. Furthermore, the numbers say Galileo’s nicks with Kris and Diesis are not attributable to their sire line. Galileo has sired foals out of 53 mares that have Sharpen Up in their ancestries (the whole ancestry, not just the sire line), and the only mares among them that produced superior runners by Galileo are those that have Sharpen Up descending through either Kris or Diesis. None of the 27 mares that have Sharpen Up through strains other than Kris or Diesis produced a superior runner by Galileo. Yet, Galileo’s combined strike rate with Kris and Diesis is 6/24 (25% superior runners).
Overwhelmingly, the numbers point to Doubly Sure as the key factor, and that’s the proof that Cape Blanco is bred from a simple nick with her son, Presidium.
Posted by Roger Lyons on Thursday, May 20, 2010 at 12:01 pm.