Faced with a big field of runners, what’s your usual reaction? Could be that it’s a groan because you’re going to have to plough through the form of 14 or more runners.

How to slash the field and get rid of the “also rans” in one go? Not so easy a task. Many punters will simply concentrate on the first few favourites and more or less ignore the rest.

This has its drawbacks. In any field of runners, you should examine at least six chances. How to find those six chances without first of all going through the entire field to ferret them out?

Well, there are no hard and fast answers, but I suspect that we can use a method, which will help us “trim” down a field and gives ourselves a big chance of a collect. The approach I am going to outline is based on the work of Eric Bowers, a contributor to the popular UK monthly Smartsig.

Eric wrote in a recent issue: “In form assessment, we occasionally get so tied up with complicated rocket-science ideas and mathematical configuration formula that we lose track of the basic principles involved in race evaluation.

‘I was reminded of this the other day when I was asked how I dealt with the apparent increase of races involving large fields, and the added time required for race reading and interpreting of the form.

“I did introduce and explain in a book during 1990 a methodical system or method (the choice is yours) that reduces all large handicap fields to a workable level. I found there was a distinct relationship between the Class scale of a race and the forecast betting odds range, which can be exploited.

“I have used this method with great success over the last 17 years with not one losing season.”

Eric’s idea is very simple, easy to work out, and can be used for races over any distance.

This is how he explains it (and remember that he is talking about UK racing): “Take a typical 15 runners handicap race at any distance, and depending on a reasonable linear weight spread. The middle five runners are racing within their own class, those towards the top are below their class, while those at the bottom are above their class.

“All things being equal, the Official Handicapper has allocated the top weight to the horse he considers has had the best acceptable form in the past. Other horses are presented on a sliding scale at lesser comparable weights depending on their past form.

“The full weight range of a handicap race normally covers about 30 pounds (15kg) and it is generally acknowledged that the greater percentage of races are won by those horses placed WITHIN THEIR OWN CLASS or BELOW THEIR CLASS.”

Eric says the UK betting forecasts are to be taken as a “very specialized assessment”. They are, he points out, “without doubt, the most complete guide to finding winners and it is remarkable how reliable and accurate these odds are”.

I might chip in at this point and say that I don’t have the same confidence in the pre-race betting markets published in Australian newspaper guides and formguides!

Anyway, to continue Eric’s viewpoint. He says: “The normal range of odds covered for a typical 15-runners handicap is around 2/1 to 33/1. Again, the greater percentage of winners is towards the front end of the market; outsiders at 20/1 plus are rare.

“To explain the logic behind my system, I say the ratings produced are a balance between overall form and recent form. To obtain this rating, we use the two most experienced assessors of form in the racing world, namely the Official Handicapper and the expert who compiles the UK Racing Post betting forecasts.

“The weights assessed…are biased more towards overall form and less towards recent form. The betting forecasts, however, are biased more towards recent form and stable information and slightly less towards overall form. Therefore, to produce a rating we have to obtain a balance between the two.”

Eric’s idea is that you select handicap races with 10 or more runners and mark the weight difference in pounds (or kilos in Australia) between each horse and the topweight. The top weighted horse(s) is obviously marked as a ZERO.

When you reach the bottom horse you can cross check that the number you have agrees with the total difference between top and bottom weights. The weight rating is then added to each horse’s pre-post odds.

Eric says: “The aim is to reject approximately 50 per cent of the runners (not always possible to be so precise). We commence by rejecting the horse with the highest rating number and proceed down through the numbers to the 50 per cent mark. It’s around this cutoff point where you are forced into making a decision as to exactly what point you’ll close down.

“In the majority of cases, especially the higher field races, there will be no problem.”

Now, that’s the summary of what Eric Bowers does to slash a field in half. It’s an interesting exercise. It obviously works well in the UK, and I think it has huge potential in Australia. We must keep in mind, however, that Eric is not suggesting that you accept the horses in rating order (lowest rated the best and so on) but that you use them as the horses to be considered in a race.

His major point is that the exercise reduces the bookmaker’s “over round” as it trims the field down to a manageable list.

He says: “The elimination process obviously rejects the rank outsiders yet retains most of the favourites. The area where it has the most telling effect is the middle range. It differentiates the win potential between those top class horses in the middle of the odds range who are dropping down in class, and the recent winners at the bottom of the scale who are going up in class.”

Let’s have a look at some Aussie races. Using morning radio prices from Radio TAB in Brisbane, the fourth race at Rosehill came up with the following ratings:

JETEYE 8.0, BREAK THE BARRIER 7.5, ABOVE DECK 6.5, CEZANNE 9.5, SLY DOG 10.5, DUCKS 12.0 and TAKEN AT THE FLOOD 13.5. The rest of the field was eliminated.

How did these ratings come about? Well, Jeteye was 8/1 in the market and being the topweight he had a 0.0 weight rating, so his final rating was 8.0. Break The Barrier was a 6/1 chance and had a weight rating of 1.5 (that is, with 57.5kg he was 1.5kg below the topweight), so his final rating was 7.5.

Above Deck came out the best rated runner. He was 4/1 in the market and had a weight rating of 2.5, so his final tally was 6.5. And so on. The result of this race was Above Deck winning with Sly Dog 2nd and Cezanne 3rd.

Naturally, in most instances this procedure is going to zero in on the best-fancied runners in the morning market, as it did in race 7 at Moonee Valley on July 30. There were 10 runners and four were axed immediately after getting final ratings of 23.0, 14.0, 19.0 and 19.0.

Taking the 50 per cent line, I then eliminated two runners that were on 13.0 and 14.0. That left me with four runners:

MILKSHAKE 2.5, HUNTER HERMITAGE 8.0, EMERALD JACK 5.0 and CAPRIZZI STRIP 6.5. Emerald Jack won at $3.80, Hunter Hermitage (9/1) ran 2nd, and Caprizzi Strip (3/1) ran 3rd. The trifecta paid $98.

There will be races where your assessed half dozen or so runners will not provide the winner. This is to be expected. But we are looking at a long-term strike rate strategy and in the long-term your assessments will provide the winner, often in the first two or three, many times.

Let’s look at Rosehill (race 2) on July 30. There were 10 runners, reduced to nine after scratchings, and the final assessments immediately culled Mr Marvellous (22.0) and Pimpala Player (23.0). The next one down was Rectagonal at 8.5 and I decided he could go. That left the race to be decided between six runners, with the top pair CASHOUT on 3.5 and ACTION SHOT 4.5, followed by OCTZANO and DESETTA both on 6.0.

The result was that Action Shot won at $6.10, Cashout ran 2nd at 13/4 and Desetta was 3rd at 3/1. The trifecta paid $107.00.

Again, this was a race in which the best-fancied runners scored and this, of course, is the point Eric Bowers wants to make: If you wish to succeed you MUST concentrate on the horses that history shows are going to finish in the money. Whether this approach will appeal to many punters I simply don’t know. You may well decide it’s easier just to stick to the top six in the betting market.

I’ll be testing it out in greater details in the weeks and months ahead, to see what sort of overall strike rate can be achieved. My idea is that I use a cutoff point of over 50 per cent. So if the range is up to say, 33 weight ratings points, I will only use those runners with final ratings of 13.0 or less or with a top rating of, say, 25 I will only assess those runners who qualify with 10.0 or less.

To sum up, then: Get your weight ratings first. Work down from the top weight and give it 0.0. If the next runner is 1kg below the topweight it gets 1.0, if the next horse is 2.5kg away from the topweight it gets 2.5 etc.

Once you get all the weight ratings, simply add the pre-post price to each rating for each horse. So, a horse at 4/1 with a weight rating of 2.0 will get a final rating of 6.0.

In future issues of PPM, I’ll bring you more reports on how things have gone. I think it will be a fascinating test period.

By Martin Dowling