Longest Losing Streak

A. There is a simple formula you can use to determine the longest winning / losing streak of an event. Here's the formula:

Log(RUNS) / -Log(PROB)

Where Ln is the Natural Logarithm Function, RUNS is the maximum number of runs in a sequence and PROB is the probability of the event happening.

e.g.

In the past 10 years on the Flat Turf there were 33,084 races so if we wanted to check the longest losing run of favourites over this period assume RUNS = 33084

The strike rate of favourites on the Flat Turf during this period was 31.7% so the probability of them winning is 0.317. But as we want to calculate the longest losing run we need the probability of them losing. This is simply

1 - prob of winning = 1 - 0.317 = 0.683

We therefore set PROB = 0.683

The formula is now:

Log(33084) / -Log(0.683)

You can work that out with a calculator or Excel. If you do you will see that the answer is

27.3

What this means is that in a sequence of 33,084 races (10 years worth of results) we can expect the longest losing streak of favourites to be around 27.

Real World Test

The Flatstats Laying Systems section has a report which shows the results of laying all favourites on flat turf. Running this report reveals the following results:

Total Runs 33,084
Total Correct Lays 22,609
Lay Strike Rate 68.3%
Max Winning Run 28

The real world test saw a longest winning run of 28 which is near enough what the formula above produced.

Laying Favourites System