 Last month I left you with the promise of detailing what would happen if I changed the percentage figures when pricing a field.

In order to provide this information and have you understand how the procedure works I have to go back to how Don Scott used to do his pricing.

On page 237 of The Winning Way Don provided a chart called Table Of Advantages To Chances in which he provided the decimal odds involved when lining up the expected beaten margin of each horse in a field as a kilogram figure.

I have reproduced his two main columns for horses up to 4.5kg which, at 1.5kg per length, represents 3.0 lengths.

Exp Mgn Dec Odds Exp Mgn Dec Odds
0.00kg 1.00 2.5kg 0.50
0.50kg 0.90 3.0kg 0.40
1.00kg 0.80 3.5kg 0.33
1.5kg 0.67 4.0kg 0.25
2.00kg 0.57 4.5kg 0.20

In Appendix D on page 412, Don provided a conversion table of beaten margins into kg figures:

Exp Mgn Kg
Shthd or less 0.00
Hd to lng nk 0.50
0.5L to 0.75L 1.00
1.0L
1.50
1.25L 2.00
1.5L to 1.75L
2.50
2.0L 3.00
2.25L 3.50
2.50L to 2.75L 4.00
3.00L 4.50
OK, so let’s make up a hypothetical field of eight runners and we will simply call them Horses A to H. We have done the form on this race and in order to apply the Don Scott methodology we have to visualise the beaten margin between each of the runners. Let’s go with this assessment:

Horse A to win = 0.00kg = 1.00 Decimal Odds
Horse B to be beaten by a long neck = 0.50kg = 0.90 Decimal Odds
Horse C to be beaten by 0.5L = 1.00kg = 0.80 Decimal Odds
Horse D to be beaten by 1.0L = 1.5kg = 0.67 Decimal Odds
Horse E to be beaten by 1.25L = 2.0kg = 0.57 Decimal Odds
Horse F to be beaten by 1.75L = 2.5kg = 0.50 Decimal Odds
Horse G to be beaten by 2.25L = 3.50kg = 0.33 Decimal Odds
Horse H to be beaten by 3.00L = 4.50kg = 0.20 Decimal Odds

At this stage, we have JUST visualised the beaten margins and converted them to a kilogram figure. If you were a bookmaker at a racetrack where the number of punters only numbered 1,000 then realistically you would price your field to 120 per cent or even more, but let’s just stick with 120 per cent. In order to calculate your prices as a bookmaker you would apply this formula for every runner.

Firstly, you have to add up the decimal odds for all runners which in this race total 4.97. Divide the decimal odds of each horse by 4.97 and multiply that figure by 120 (the percentage you are pricing to).

For example:

Horse A: 1.00 divided by 4.97 x 120 = 24.14% = \$4.10
Horse B: 0.90 divided by 4.97 x 120 = 21.73% = \$4.60
Horse C: 0.80 divided by 4.97 x 120 = 19.31% = \$5.20
Horse D: 0.67 divided by 4.97 x 120 = 16.17% = \$6.20
Horse E: 0.57 divided by 4.97 x 120 = 13.76% = \$7.30
Horse F: 0.50 divided by 4.97 x 120 = 12.07% = \$8.30
Horse G: 0.33 divided by 4.97 x 120 =  7.96% = \$13.00
Horse H: 0.20 divided by 4.97 x 120 =  4.82% = \$21.00
Totalling 119.96%

Based on the assessed margins and using Don Scott’s formula  the dividends I have shown above would be the prices displayed by Mr  Bookmaker. Based on the percentages for every \$119.96 received from the punters Mr Bookmaker pays out \$100.

That’s fine for the bookmaker but we are punters and this is where Don Scott reversed the above process by pricing his chances to 80 per cent.

Now you know the formula you can do the calculations to check my figures but as Mr Punter the prices, based on 80 per cent, would be:

Horse A = 16.09% = \$6.20
Horse B = 14.48% = \$6.90
Horse C = 12.87% = \$7.80
Horse D = 10.78% = \$9.30
Horse E = 9.17% = \$11.00
Horse F = 8.04% = \$12.00
Horse G = 5.31% = \$21.00
Horse H = 3.21% = \$31.00

(Note: In the chart  provided last month, I have not calculated dividends like \$10.10, \$10.20 and so on in order to keep the chart size down: there is nothing stopping you to add to the chart yourself.)

In the situation where Mr Book-maker wants \$120 into his bag in order to pay out \$100, Mr Punter needs to reverse the process and receive \$100 back for an outlay less than \$100. Don Scott believed 80 per cent suited his style of betting and what he wanted was to collect \$100 for every \$80 he outlaid.

The first thing you will notice when comparing Mr Bookmaker and Mr Punter’s prices is that there is quite a disparity and, of course, so it should be based on the different percentages. As the punter YOU must decide what percentage you want to set by asking yourself, “Am I prepared to outlay \$80 to win \$20 or is that too tight for MY comfort?”

Each punter would answer that question differently. Punter A would say 80 per cent suits me just fine because I don’t mind accepting about 3/1 my A selection while Punter B might say, “I will not accept less than 5/1 ANY horse and I really, really only want to back horses I have rated as top value.” Punter B might say, after some experimentation, that 50 per cent is the figure he wants to adopt.

In that case the prices would start with Horse A = 10.06 per cent = \$9.90 thus Punter B will not accept less than \$9.90 (nearly 9/1) about his A selection and by the time he got to Horse H he would be requiring 2.01 per cent or \$51.00. I will let you work this out for yourself: just follow what I have shown you so far.

Personally, I think 50 per cent borders on the absurd; however, it is not my brief to be telling punters what percentages they should be betting as the choice is theirs because, quite simply, it is their money!

If we use 60 per cent we have Horse A at 12.07 per cent = \$8.30; if we use 70 per cent we have Horse A at 14.08 per cent = \$7.10; if we use 80 per cent we have Horse A at 16.09 per cent = \$6.20 and if we use 90 per cent we have Horse A at 18.10 per cent = \$5.50.

All of what I have written so far is on the impossible premise that you, as the punter, will be able to back every runner at the prices you set and make your desired profit EVERY race. However, the reality is different. There will be some races where you might only back two runners out of a field of eight and miss the winner; thus, over the course of a year you will not be guaranteed the profits based on whatever percentage you use, but at least in the long term you are only accepting what you consider as value.

The two articles I have written on this might at first seem far too hard for you to calculate at first glance but let me assure you that if you can just imagine what margins you think there would be if you were looking at a photo finish of the race then you have actually done the hard work.

The rest is just simple usage of a calculator and in no time flat you will be pricing a field quite quickly. Those of you with Excel experience, or have a punting friend who does, could write up a simple program to do all the calculations for you. I am no expert in the area but even I know these days it’s a fairly simple process.

Naturally, the extra hard part of this process is deciding which horse should finish ahead of any other horse and that is where form analysis becomes the key point – but that is another issue.

Good luck with your pricing; I hope I have given you some ideas on how you should approach this style of punting.