February 1, 2006.
by Gord McPherson
One of the key tools in our CPR evaluation process is reliance on the top AER horse in the race (hereafter the "TAER" for convenience). In fact in my own handicapping I always start with a look at the TAER horse to get an idea of how much of a factor it is likely to be. Over the years we have done several studies, and invaribly it has fared pretty well in conjunction with the support of the crowd, as one of the crowd's top two or three favorites. That TAER angle formed the backbone of our CPR methodology published here at the beginning of the year.
While the results for some aspects of the CPR method have been inconsistent, the results for the key TAER angle has continued to perform well. So I have done an analysis of the last week's worth of races to prepare this update.
As I have advised you elsewhere (see the links to Chalk Talk or CPR on our front page) the AER calculation is based upon the findings of Bill Quirin published in his 1979 seminal work Winning At The Races. He found a strong correlation between average earnings per race and performance, especially when combined with a good last race. Our AER essentially converts that average to a ratio of the highest score, multiplied by 100. Thus the top AER (our TAER) will have a rating of 100, and each other horse will have an AER that is a percentage of that score.
The TAER does not stand alone as an indicator. In a number of cases it is outdated based upon a horse's better days and has nothing to do with current form. Thus Quirin's decision to combine it with a last good race. We have approached it differently, relying on there being an indication from the tote board that the crowd considers it to be a logical contender. Our studies have found consistently that when the TAER is also one of the top 2 or 3 choices of the betting public that this is a fairly consistent and reliable indication. Alternatively you can use a requirement that the odds should not be more than 4 or 5 to 1.
For this study I looked at a random sampling of races at the tracks we cover with our daily ratings for the week ending January 28. The races omitted were those with multiple scratches, multiple first time starters and off tracks. This left a total of 181 races in the study. The results are set out in the Tables below. The first represents some general findings, and the second focuses on the more productive categories of older horses running on dirt
In the similar April 2005 study races for 3 year olds and maidens were omitted as unreliable due to the inconsistency of such fields. Maidens by definition have not yet proven they can win. I have always found that three year olds are not dependable until half way through the year. The results confirmed that those races should be excluded with the TAER only winning 17.4% of their 51 three year old races with an average return of $0.66 for each imagined $2 win wager. For maidens the win percentage was higher at 27.5% of 40 races, but the return was still only $1.17 relying on low priced winners. It also appears that the TAER didn't fare well in turf races either, winning just 16.7% of 28 races, for an average return of just $0.93.
The results excluding those categories and focusing on the top 3 choices of the crowd (C1, C2 and C3) for races involving older horses on dirt are similar to those in the April 2005 study with some interesting differences. Most notably the third choice (C3) did not prove to be reliable but there were just 11 races, all failing to win. The strongest return seems to generate from the C2 horses, especially combining with the C1 horses that meet minimum odds requirements. References to RTG refer to the performance ratings such as + or ++. The DLR continued to be a reliable indicator of readiness while the FW score was less useful. In the previous study it was noted that for the TAER horse returning in less than 28 days was optimal. However in this study there did not seem to be a problem with those returning in 35 days (5 weeks rather than 4) of their last race. Of course there is no hard and fast line to be drawn at a specific date after which a horse should be discarded. The factor is really a continuum and there is little to just between say 28 days and 30. Each horse needs to be looked at as an individual. However, it does seem clear that the longer a horse has been off the more suspect his return as a TAER selection is.
| Number of races | Wins | Win % | Avg Mutuel | Return per $2 Win Bet | |
| All TAERs | 181 | 54 | 29.8 | 1.64 | |
| 3 Yr Olds | 46 | 8 | 17.4 | 0.73 | |
| Older Horses | 135 | 46 | 34.0 | 1.95 | |
| Maidens | 40 | 11 | 27.5 | 4.38 | 1.20 |
| Turf | 24 | 4 | 16.7 | 4.90 | 0.93 |
| Dirt | 157 | 49 | 31.2 | 5.49 | 1.71 |
| No RTG | 40 | 4 | 10 | 6.55 | 0.75 |
| RTG + or better | 141 | 50 | 35.5 | 5.41 | 1.92 |
| RTG ++ or better | 92 | 35 | 38.0 | 5.53 | 2.10 |
| RTG +++ | 37 | 20 | 54.1 | 5.10 | 2.75 |
| Odds <= 5-1 | 134 | 52 | 38.8 | 5.05 | 1.96 |
| All C1 or C2 | 118 | 51 | 43.2 | 4.96 | 2.14 |
Once we filter out all the races which are either three year olds, maiden or on the turf, or a combination of those, we are left with 118 races. Those races are all run on dirt by older horses. A breakdown of those races is set out in Table 2.
On Dirt | Number of races | Wins | Win % | Avg Mutuel | Return per $2 Win Bet |
| All races | 118 | 39 | 33.1 | 5.82 | 1.92 |
| DLR > 28 | 60 | 17 | 28.3 | 5.34 | 1.51 |
| DLR > 35 | 47 | 10 | 21.3 | 5.63 | 1.20 |
| DLR <= 28 | 58 | 22 | 37.9 | 6.20 | 2.35 |
| DLR <= 35 | 71 | 29 | 40.8 | 5.89 | 2.40 |
| No RTG | 23 | 2 | 8.7 | 5.50 | 0.48 |
| RTG + or better | 95 | 37 | 38.9 | 5.84 | 2.27 |
| RTG +++ | 23 | 13 | 61.9 | 5.59 | 3.16 |
| C1 or C2 | 81 | 37 | 45.7 | 5.22 | 2.39 |
| C3 | 11 | 0 | 0 | 0 | 0 |
| C1 or C2 with RTG + or better and DLR <=28 | 35 | 20 | 57.1 | 5.13 | 2.93 |
| C1 or C2 with RTG +1 or better and DLR <= 35 | 45 | 26 | 57.7 | 4.84 | 2.80 |
| Odds > 4 to 1 | 36 | 2 | 5.5 | 16.90 | 0.94 |
The results of this study are relatively consistent to the 2005 study in finding the TAER (top AER) horse to be a good selection, tending to return a profit on flat $2 win wagers provided it is returning within a reasonable time to race after its previous race. In terms of the CPR criteria: class is satisfied by the top AER score and the horse being one of the top 2 crowd choices; performance is satisfied by the horse having a minimum + performance rating; and readiness is satisfied by the return within 28 or 35 days (depending on where you wish to draw that line).
Our previous study showed that it was advisable to set a minimum odds requirement of 3/2. However the current study would not have benefited significantly from that. Imposing an even money requirement would have reduced the number of selections (using a DLR of 35 or less) to 40, with 20 winners and an average return of $2.93. Using a 3/2 minimum would have resulted in 29 selections of which 13 won for an average return of $2.81. It is probably advisable to consider using at least an even money requirement, since the previous study suggests merit to a minimum odds approach.
Using the 35 day DLR guideline there would have been a TAER contender in 45 of the 181 race sample which is just under one quarter (24.9%) of the races. In a method focusing on low priced solid crowd choices that have an edge the win percentage and the average return are encouraging.
The following guidelines are suggested for considering TAER for
contender selection:
There is one other type of horse that you may wish to include as a TAER contender. That is any horse that has a +++ rating, especially if the top AER horse is eliminated because of missing RTG, the DLR or it is not in the top 2 or 3 crowd choices. The remaining +++ by definition must have a AER of 90 or better, have managed to run at par and at the distance and is returning in 28 days or less. Clearly if the top AER horse has been eliminated, this type of +++ is a fair substitute.