Further to my review of Beat the Racetrack for place pricing on Betfair, I present a brief study of odds in the Betfair horse racing place market.
In the chart below (click to enlarge), we see two lines representing the expected percentage chance of placing in a horse race, derived from the Betfair place odds, and the actual percentage of horses placing, derived from results.
There is a good fit between the public's perceived chance of a horse placing and the actual outcome.
The data for the chart came from the following table (click to enlarge),
where Rank is the percentage range in which the odds fell. Exp is the expected percentage chance of placing and Act is the actual percentage of placers from the racing results. There were 8193 runners in the sample.
There follows a similar chart (click to enlarge) derived from the Henery place model for the same runners in the races charted above.
As you can see, there is no discernible difference between Betfair odds and the Henery estimation. The Betfair place market is efficient enough to prevent the use of place pricing models to improve upon the public's perception.
This doesn't mean to say that runners can't be filtered out as being value bets (as in the win market) but you won't achieve it using any of the Tote place/show market pricing models.