Category:Form Analysis

From AusRace

Ability Ratings

A Matter Of Merit (1) - Merit ratings & How They Work

From Lengths To Kilos

“Difference of opinion is what makes horse racing.” It’s an adage that holds true today as much as a hundred years ago. Racing without debate, heated or not, wouldn’t be the same. Controversial these days are Merit Ratings, a big debating point being how the official handicapper arrives at his ratings. Here are some ideas, writes Karel Miedema.

Handicapping is the art of bringing horses together, and making fields competitive. A ‘good’ handicap is all about perception. The question which must be asked: “What do people think before the race?” A ‘good’ handicap is when there are plenty of runners in the field, and no short-priced favourite. An open race. How do we arrive at the weights for such a race? The official handicapper must work on the assumption that most horses are inherently consistent, and reproduce their best form for periods at a time - if not all the time.

By measuring what is regarded as normal form, and expressing it in a figure, horses can be matched against each other and the playing field be levelled. The measure the handicapper uses is weight. Each horse has a Merit Rating (MR), an assessment of the ability shown on the track. The Merit Rating is expressed in half-kilos.

Horses with the same MR are assumed to have similar ability. Each Merit Rating point equals half a kilo. Merit Ratings are calculated by comparing the performances of horses in a race. One horse beats another. The difference in lengths between the two can be translated in half-kilos, using a formula which has stood the test of time. It is important to understand that a length has different weight equivalent over different distances. That makes sense, as it becomes more difficult to carry weight the further the distance. Carrying a water-bucket once round the block may be fine, but the second lap will tax your muscles, slow you down.

One extra kilo weight in a sprint has far less effect than one kilo in a staying race. It may sound strange that the performance of a horse weighing 500kg, who carries a jockey and saddle weighing some 50kg, can be influenced by changing the weight carried in the saddle by a single kilo. This is because the spine of a horse acts in unison with its stomach muscles, creating what is in effect a bow and string effect. Stomach muscles affect the stride. More pressure on the ‘bow’ asks for more effort by the horse to stride freely. A little extra weight goes a long way to make things more difficult.

The conversion table used by a typical handicapper will look something like this.

Distance...1 length equals half-kilos 1000m .... 4 1600m .... 3 2000m .... 2 2400m .... 1 or the other way round: Distance...1 half-kilo equals.lengths 1000m .... 1/4 1600m .... 1/2 2000m .... 3/4 2400m .... 1

So: On average one kilo equals one length over a mile, but less in a sprint, and more over ground. Think: In a slow run race it becomes easier to carry weight, and the ‘slowing down effect’ of weight should be adjusted to compensate. That is why knowing at what pace a race is being run is important.

Horses come into any race with an existing Merit Rating (how the base or start-up rating is arrived at will the subject of another article). The distance of the race is fixed, so the handicapper knows what weight value to use for one length. Now when the race is run the horses will beat each other by a certain number of lengths, which can be translated into half-kilos using the formula. If all horses carry the same weight, then calculated difference from lengths-behind into half-kilos will equal the difference in Merit rating between the horses.

For example: Horse A and B race over 1600m; both carry the same weight; Horse A beats Horse B by 2 lengths. The two lengths difference is the equivalent of 4 half-kilos - Horse A therefore puts up a performance 4 Merit Points superior to Horse B. Now the handicapper looks at the Merit Ratings as they were before the race. He checks: was Horse A’s Merit Rating beforehand also 4 points higher than the one of Horse B? Chances are it won’t be exactly the same, but it should be close. Now comes the task of adjusting the rating. If the ‘before’ and ‘after’ MR’s weren’t the same, how should they be adjusted - if at all?

To make that decision the handicapper MUST look at the ratings of ALL horses in the race, not just those of A and B. Most commonly, he will look for the performance of a horse that finished within a few lengths of the winner and whose recent form has been consistent and reliable. That becomes his KEY HORSE, the horse whose rating is used as a benchmark.

Free My Heart A good example of this is the performance of Free My Heart when he beat Jet Master over 1600m at Clairwood. In the July panel discussion Paul Lafferty was highly vocal about the fact that he didn’t think Free My Heart had been properly ‘penalised’, and that he should have had his Merit Rating increased by six instead of the two Merit Rating points the handicapper raised his rating by.

the reasoning of taking a line through Jet Master is used, then Free My Heart’s rating should have been increased to at least the level of Jet Master’s rating. That’s what the race showed. Now for the crunch: if Free My Heart’s rating is raised to that level, then the ratings for all other runners in the same race must follow suit - they are, after all, linked together through the lengths-behind-the-winner calculation. In this case it meant that not only Free My Heart’s rating would have gone up dramatically, but those of most other runners in the race as well! Forget it. 

The only logical conclusion was that Jet Master probably ran below best, and should not be used as the key HORSE. The handicapper decided, in this case, that the more likely candidate for key honours was third finisher Glamour Boy. If Glamour Boy ran to his ‘normal’ form, then most of the horses in the field appeared to do the same. Free My Heart’s Merit Rating increase was therefore based on beating Glamour Boy, not on beating Jet Master.

A sound decision. This example illustrates what is probably the most common mistake made by us. We assume that when a horse wins a race it automatically must have its merit Rating increased, be penalised. Wrong. IT ALL DEPENDS on the key HORSE. The winning horse could well have won easily and run below his rating, in which case it would be wrong to increase its rating. If a penalty for winning was given automatically, then it could be that several of the beaten horses might also have to go up, because of their lengths-behind-the-winner relationship.

Makes no sense. In handicapping there’s no such thing as a penalty. Re-assessment to achieve optimum competitiveness - that the name of the game. 

Don’t forget: the handicapper rates ALL races, not just handicaps. After each and every race he attempts to achieve a ‘best fit’ for the Merit ratings of all horses in the race, not just for the winner or the first two home. Over time, the handicapper will build up a history of each horse, a solid background to its apparent ability shown on the track. So when you see a short-priced favourite in a handicap race (where the handicapper has set the weights to give every horse the same chance of winning), pay attention.

Either the handicapper has slipped up, or - much more likely - the market is wrong. Often you can use that knowledge to your benefit. The Ability Ratings (AR) in Sporting Post are calculated in much the same way as the official Merit Ratings. Sometimes opinions concur strongly, sometimes they differ - either way useful betting opportunities arise. Keep your eyes peeled.

A Matter Of Merit (2) - Merit ratings & How They Work

The Magic Of Rule 54.3

How Weight-for-Age predicts a horse’s improvement

When a topclass juvenile gets beaten over a bit of ground early as a three year old, when racing against its elders, it is amazing how many racing experts blindly walk into the Weight-for-Age trap. “Disappointing run,” we hear. Or: “What went wrong?” Fact is that Weight-for-Age (or WFA for short) plays as much a role in the performance of a horse as weight does, writes Karel Miedema.

WFA is best defined as ‘the physical progress any horse makes as it matures’. Just in the same way as a young human athlete, under conditions of continuous exercise, improves his strength of bone and muscle as he matures. The only difference is that the thoroughbred is uniquely precocious in terms of maturing rate: by the age of 18-24 months the horse has achieved 95% of its mature height and weight, and by the end of its third year full maturity will be reached. To apply Weight-for-Age in the context of racing, it is necessary to express it as a function of weight carried.

The question then becomes by how much weight an older horse must be disadvantaged to make the younger horse competitive. If no allowance was made, a mature older horse would always beat a younger one - just as a schoolboy rugby player wouldn’t stand a chance in a Five Nation’s match, EVEN IF the schoolboy stands out in his own environment and is already talked of as a future Springbok player. 

The application of the Weight-for-Age principle dates back to about 1860, when Admiral Rous controlled the affairs of the English Jockey Club. Rous was a handicapper through and through, and by experiment arrived at a relationship between age and maturity, expressed in weight. His original work has stood the test of time with only minor alteration. It is known as the Weight-for-Age scale, and incorporated in our Rules of the Jockey Club as Rule 54.3. The scale takes not only age into account, but also the distance over which races are run. This is understandable, as stamina comes with maturity, and younger horses are at a greater disadvantage the further they have to run.

An example. The official WFA-scale, for races from 1000 to 1200m, shows that sprinters reach maturity by the end of their 3yo career. In terms of weight disadvantage they had been catching up with their elders at a rate of one half-kilo per month during their 3yo days, and about 2 half-kilos per month when they were still two year olds. For instance, in the first month of their 3yo career (August) the WFA difference with a 4yo is officially set at 14 half-kilos.

In other words, to make two horses of equal ability (as reflected in their Merit Rating) competitive, the older horse must carry 14 half-kilos (7kg) more than the 3yo. By January this has reduced to 7 half-kilos, and come July there is just one half-kilo to go.

Now look at races from a mile (1600m) to 1800m. The August WFA-allowance is 18 half-kilos (9kg), reduced to 10 half-kilos in January, and 2 half-kilos in July. When Badger’s Coast beat El Picha in the J&B Met over 2000m last January, he was at an official WFA-disadvantage of 12 half-kilos, while 4yo El Picha still had 1 half-kilo to go. By the time the July was run, El Picha was ‘mature’, Badger’s Coast had 3 half-kilos to come. Which means that the overall difference between the two had gone from 11 half-kilos in January to 3 half-kilos in July. It illustrates just how far Badger’s Coast ran below best in the July if his Met-run is taken as gospel (Badger’s Coast carried only half a kilo more in the July, El Picha’s weight stayed the same).

Not all horses grow to maturity at the same rate. Sprinters get there quicker than stayers (just think of the age at which Comrades runners are at their peak). Some horses are nippy, early types who make little progress as they get older (the only time to get a win out of them is early at 2). Others are gangly, backward types who makes unusual progress once they grow into their frames.

A look at young horses in the parade ring before a race can be tell-tale. Think of London News, who ran a few times late as a 2yo and showed nothing. And of Bush Telegraph, who destroyed his opposition as early as January of his 2yo career. Then there last season’s champion 2yo Roaring Sands, an early maturer who was simply unable to make progress from two to three. Horses for courses. On average, though, it is fair to assume that for most horses the progress towards maturity takes place at a predictable, even rate. SO: The average horse matures at a rate of about half a kilo per month, sprinters reaching maturity earlier than staying horses do. THINK:

in a slow run race it becomes easier to carry weight, so the younger horse will be at less of a disadvantage in terms of weight-for-age. That is why knowing at what pace a race is being run is important. A slow pace gives the younger horse an advantage.

Admiral Rous (1791-1877) - father of the Weight-for-Age concept In a book, Law And Practice of Horse Racing (1850), Rous wrote: “A public handicapper should be a man of independent circumstances, in every sense of the word, and beyond suspicion of accepting illicit compensation for favours received; attached to no stable, a good judge of the condition of the horse, but with a more intimate knowledge of the disposition of owners and trainers, he should be a spectator of every race of any importance, and his station should be at the distance-post, where horses are pulled, not at the winning-post where they are extended; he should never make a bet, and he should treat all remarks which may be made about his handicap with the utmost indifference.” (distance post: marker a furlong from the finish; racing in the early days was conducted in heats; if the winner of one heat finished while another horse hadn’t yet reached the distance post, the beaten horse was ‘distanced’ and not allowed to race in the next heat)

How does the handicapper apply Weight-for-Age?

Merit Ratings reflect a horse’s ability in comparison with horses of its own age. There are good horses, there are bad horses, and then there is the average horse. The latter is pivot around which all else turns. Take the Merit Ratings of all horses of the same age, add them up, divide by the total number of horses of that age and you get an average Merit Rating for the age group. Assuming that an average horse really is an average horse, then the average Merit Rating from one age group to another will not change. Within its own age group an average 2yo is as good as an average 3yo is in its own age group.

They have the same average Merit Rating. That is the KEY. Within each age group, every horse’s Merit Rating can be compared against the Merit Rating of the average horse. That shows how many half-kilos better (or worse) a horse is than average.

But the ACTUAL RATING also shows how the horses in different age groups compare. A 99-horse in the 3yo age-group is of the same ability as a 99-horse in the 4yo, or 5yo, or 2yo age group. The thing is, when they race against each other weight-for-age should be applied. This happens in weight-for-age races, but it doesn’t happen in many other races: maiden races, graduation, progress, or any other race which IS NOT a handicap.

The official handicapper of course does apply weight-for-age in handicap races. When horses with the same Merit Rating meet, their weight should be the same - except when they are of different ages. In that case the handicapper will deduct the weight-for-age deficit (from the official scale, according to time of year and distance of the race) from the weight of the younger horse. It soon is August, when the young 3yo’s start meeting the older horses with regularity.

Over a mile the weight-for-age deficit for 3yo’s is 8.5kg, or 17 Merit Rating points.

THINK: To beat a 4yo with a Merit Rating of 70 (not too good, in other words), a 3yo must have a rating of at least 87 (pretty good, in other words) if they meet at level weights. To beat a 4yo with a Merit Rating of 85 (pretty good), the 3yo must have a Merit Rating of at least 102 - which approaches classic calibre. So unless a 3yo in August gets plenty of weight from a 4yo, beating the older horse takes some doing, especially over some ground. It pays to follow older horses early in the season, however moderate they seem to be!