Hi All

Like many others, I use an Excel based ratings system to determine my picks for any given race (thanks to Shaun on this forum for technical assistance with this a few weeks ago).

Results so far are encouraging and my top 4 rated will produce the winner 68% of the time based on a sample of 200 races. POT of 21% backing all four horses to win to level stakes (using TAB divs as basis for calc). No doubt this'll reduce substantially when I eventually find the courage to put some cash on my selections!

My question relates to the concept of value. With a 68% chance of one of my Top 4 coming in the winner, value theory (as I understand it) suggests I should bet only when the combined odds on offer are below 68%? Is this correct? I understand that when backing a single horse, value can be achieved when my assessed odds for a specific horse are lower than the odds on offer from the TAB/Bookmaker but I wonder whether this approach is valid for backing four horses in a race when my assessment of their % chance of winning (68%) is based on a historic trend in a relatively small sample as opposed to taking each race and each horse on its merits and trying to establish value on a race by race basis.

Any thoughts on this? I've rerun the spreadsheets to see what impact this approach has on POT and it does increase (to 31%) but the number of bets is substantially reduced so could just be a quirck.

Welcome some feedback

Many thanks in advance