Tuesday, May 08, 2007

20-20 Reckoning

Just as we do with our handicapping at Kennedy's Corridor we feel it is only responsible to review methods and suggestions given before a Derby. So many people are free with the advice but they don't keep score. They change the topic if they lost and they beat their chest if they won. Here we just present the numbers, that is why every weekend you get to see a review of how you might have done if you bet on the recommendations given. You also get to see the overall track record of the selections made so you can decide whether it's worth listening to or not.

Most people will easily recognize that the Derby 20-20 system did not have a vintage year. Scat Daddy, the top ranked horse ran 18th. 3 of the top 4 ranked horses ran poorly. Street Sense was ranked the co/10th choice. But does this spell the end for the 20-20 system? Personally I would say not at all, for this year was unique in many ways and the results it produced were really not out of line with what others years have looked like in the past. It is easy to look back at the past results and say, "okay it had 9 of the last 11 winners ranked at the top that means this year it should work" This is an assumption and a faulty one at that. The system actually has losers so you must expect that any given year could be a loser. One interesting thing to note is that prior to this Derby many people compared it with 2005 in that they felt anyone who lined up had a shot at winning. Interestingly enough the profile did about as well in 2005 as it did in 2007. The only difference was the starting price on Giacomo was much higher than Street Sense's.

Hard Spun and Curlin were right in line with what other horses scored who hit the frame so I see no reason to have an in-depth introspection into their statistical confirmation. But there is no question that Street Sense was the first big favorite who won despite being negatively ranked by the system. There are 20 factors and Street Sense failed on 5 of them (for his score of 10) Let's look at the factors that he conflicted on and see if maybe there are explanations.

#3 The entrant must have run within 3 Beyer points of the average two turn prep winning figure in their last prep.

The number he had to run in his last prep in order to qualify for this one was a 94. He ran a 93 in one of the most bizarre prep races in recent years. Both the pace of the race and the fact that Beyer Figures tend to be lower on Polytrack conspired to make him just shy in this regard. All the Beyer factors need an asterisk beside them because of the Polytrack variable.

#4 Beyer difference of no worse than -2 from second-to-last race to last prep race.

Again this comparison is difficult because of the odd number in the Blue Grass. His race in the TB Derby was on conventional dirt with a regular pace. I'm not sure if you can hold his declining figure against him. The factor is meant to expose horses who are going the wrong way form wise. He clearly didn't fit that paradigm.

#6 The entrant cannot have run the highest of their last three Beyer Speed Figures three starts back.

Essentially you don't want the horses best recent race to be 3 starts ago. But in Street Sense's case it was slightly unique as his best race came under the same conditions last year and only two of the three figures used for this factor were recorded this year. The horses who failed to qualify for this factor were a cumulative 35-2-0-0 in the Derby. If modern training techniques change much more I could see this factor becoming useless because it wouldn't indicate what it is meant to.

#7 The entrant must not have three consecutive declining Beyer Speed Figures going into the Derby.

The idea is that you don't want a horse to be going downwards in their current form cycle. However since his start third back was in a different form cycle it may not apply to him as strictly.

#18 The entrant must have earned more than 25% of their career total earnings as a 3yo.

This factor exists to try and isolate horses who were simply better as 2yo's. Street Sense earned 21% of his pre-Derby earnings as a 2yo. But then he was also nosed out of a Blue Grass win which would have seen him qualify for this factor. Also the decision to have 2 preps impacted his earnings. With another race Street Sense surely would have made a few more dollars and likely tipped the scales on the right side. However in the end I think you have to say that there was some evidence prior to the Derby that Street Sense ran his best race as a 2yo. Overall this factor is still 23-1-0-0 in the Derby. Not even the money you would have made off of Street Sense would have paid for the other losers tossed by this factor.

That is just an example of how you can look inside the numbers to get an explanation. I said it prior to the Derby and I will say it again. Horse racing is too dynamic to be completely quantified with a statistical system. Stats just give you more angles to think about and consider. They give you a basis from which to form judgements.

So was the 20-20 useful at all? Well a flat bet on every horse in the race with the amounts suggested by the system would have cost $215 dollars and Street Sense's win would have only returned $59. So you would have lost good money this year but overall you'd still be up 25.90%. Not terrible for flat betting each Derby entrant.

Another use for the 20-20 system was described by regular commenter gerry.

"i find that the group of derby contenders scoring in the 15-18 range produced a colt (sometimes more than one) who finished in the money 7 out of the 10 previous derbys// also, the group of derby contenders in the range of 12-14 produced a colt (sometimes more than one) who finished in the money 5 out of the 10 previous derbys"

"the tickets designate scat daddy as group A, colts scoring 15-18 as group B, and colts scoring 12-14 as group C// the first thing to do is to arbitrarily eliminate 2 colts from group C in an effort to have a more manageable number for that group as it relates to the cost of the tickets// the first trifecta ticket would become 1x3x4 or A over B over C // the second ticket would become 1x3x4 or A over C over B/// now if you don't like scat daddy on top then put whomever you want in as the A horse and put scat daddy into the B group bumping someone off the ticket from either the B or C group much as someone gets bumped off a flight"

Congratulations to Gerry who used his own observations about the system and a little homegrown common sense to hit the trifecta in the Derby. He relayed in a later comment that he acted on this idea and although he lost a few trifecta tickets with Scat Daddy on top he did quite nicely overall with his alternate horse in the "A" slot.

This is how a statistical system is best used, don't look for the easiest interpretation of simply taking the horse that is on top and running with it. Use common sense, your own judgement and don't take the figures as gospel. Look for useful ways to implement the information aside from simply taking the top horse. I believe I said something similar prior to the Derby but perhaps it carries more weight now that we've seen a practical outworking of gleaning value from a system even in a "losing" year.


Anonymous said...

i think this may have already been covered, if so i apologise in advance, but i was wondering about the weighting of each of the individual 20/20 factors // first, i assume there is a weighting of the individual 20/20 factors/ if so, would the weighting system or 20/20 factors be subject to change in the future based on the emergence of so many poly tracks and changes in training methods going into the derby // also, of the 20 factors comprising the 20/20 system, what 3 to 5 factors are considered by KC to be the most important/// i was out at one of the most beautiful tracks in America the other day, Arlington Park, taking wagering lumps courtesy of the newly installed synthetic track// i read an interesting comment by i believe rene douglas's agent// he said he thought douglas would do well Arlington because he had just come from riding at a poly track, the inference being that riding a poly track takes different skills than riding at dirt tracks// i hadn't thought of it that way but it makes a sense// if you can say about a jockey that he excels as a turf rider, i guess you can say that some poly track jockeys are going to be better than others/ chicaco gerry

Kennedy said...

At this point all factors are weighed equally. But that is one thing I would look at adding to help refine the 20-20.

Personally the 3 factors I consider to be the most important are #1, #9 and #20