so to find the best betting systems and keep ahead of the average punter we need to unlock the potential of Impact Value.
Impact Value is a most useful concept when assessing the merits of a horse’s chance of winning a race. The calculation of this value will give you an edge in a market which is not immediately apparent to other punters.
This technique can be applied to any sport where reliable past data is available and we start by deciding on the stats and trends we wish to analyze
A simple example is a horse that finished 3rd or 4th last time out and is now the favourite in today’s race
To calculate the impact value we employ the formula:-
% of winners with factor / % runners with factor
Now we check past data (say 6 months data from Sporting Life) for winners who were favourite and finished 3rd or 4th last time out.
If there were 10,000 runners in our data and 1000 that finished 3rd or 4th last time out who were favourites of which 250 won then
250 winners from 1000 with our factor = 25% or 0.25
1000 runners with our factor from 10,000 runners in the data = 10% or 0.10
We can now calculate the impact value
0.25 (% of winners with factor) / 0.10 (% of runners with factor) = An Impact Value of 2.5
This shows us that horses with the above factor will win 2.5 times more often than chance would suggest
This results in the best betting advantage possible in order to realize a good profit; while combining it with one or more further advantageous factors we can increase our profits even more.
For example if we take our 250 winners and discover another favourable factor such as a large proportion had run in handicaps races then this has the potential to again ramp up our winning chances.
The next consideration is to adjust the calculations of the impact value to make it an even stronger measurement.
Building on the concept of analyzing the strength of a factor in the best betting selection process is the idea of Pool Impact Value (PIV).
Calculating the PIV is similar to the Impact Value but also includes the pool or starting prices which give us an accurate reflection of a horses win chance.
The calculation is expressed as Winners/expected winners
The expected winners value is arrived at by dividing 1 by the decimal odds i.e. 1/2.50 (do not use traditional odds e.g. 5/1)
Therefore 1/2.5 = 0.40 which in percentage terms is 40%
From this we can assume that the horse has a 40% chance of winning.
Now take the number of winners in our sample and divide it by the sum of the expected winners
If the total of our expected winners is 4.0 and the number of winners is 5 then 5/4.0 = 1.25
As with Impact Value any value higher than 1.0 indicates that horses who have this factor are winning more than average steering us towards our best betting options.