As the flat turf season draws to a close, the focus of attention turns to National Hunt and All Weather Racing. Obviously my focus for the winter months is the latter code of racing although I am trialling a system to take advantage of legitimate favourites in non handicap National Hunt races.
As I’ve mentioned many times, the major reason I like punting in All Weather races is consistency. It is this consistency that yields familiar patterns that can provide that all so important edge; one of which is the draw bias.
In punting terms, read “bias” as the advantage afforded to certain stalls that have arisen due to the track configuration i.e. distance to the first turn for horses drawn on the inner rail compared to those drawn out wide or surface conditions i.e. the inner rail at Southwell can run extremely deep at times.
The popular metric of choice in differentiating the draw bias is win percentage or strike rate for each stall position.
Whilst an analysis of the success rates of horses running from each stall indicates whether high or low numbers are favoured on a particular track, this will not provide an explicit numerical value of the advantage afforded to each runner.
To put it another way for those of us who wish to incorporate stall position into private ratings, current metrics and methods publically available are inadequate. As always an independent and unique approach is required.
In researching the subject (Horse Racing: A Guide to Profitable Betting – Dr Peter May) to overcome the issue highlighted and create relative draw ratings for each stall position as advised I opted to use “average distance” each horse is beaten by the winner on a stall by stall basis.
The chart below is a visual representation of my draw ratings after applying relevant mathematical massaging of the data.
Above is my interpretation of the draw bias for recent running of the 17:35 (Breeders’ Cup Live Only On Atr Handicap, 3yo plus, 5f 20y, Class 6) at Wolverhampton on the 5th November.
Stall 1 is on the left hand side, stall 12 is on the right side. A negative figure implies a disadvantage relative to other stalls, a positive value indicates a draw advantage compared to the other stall. The size of the advantage/distance is determined by the length of the bar. Contrast this with to the typical method for measuring the draw bias for this course and distance
Experience has taught me that there is a significant low draw bias over 5 furlongs at Wolverhampton so both methods match expectation although the latter presentation does not provide numeral values that can be easily absorbed into private race ratings.
As All Weather surfaces are mostly consistent (that word again), the influences in changes of going can be largely ignored thereby simplifying the overall draw ratings model. My approach also adjusts changes in field sizes easily at the click of a button in Excel.
I have applied this technique to enhance my ratings for a while now. It may not be the key to the mint however it does provide a method of identifying specific All Weather stall biases in a quantifiable and consistent manner.
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