# FAQ

## The A/E Figure

What is this A/E figure that I constantly see within UK Horse Racing ratings and elsewhere?

A/E is, quite simply, a number which is derived from dividing the Actual number by the Expected number to see if one getting something is which more or less than can be expected.

### Basic Theory

For example, if I roll a fair die one hundred times and each time I roll a '6' I win at 5/1 and lose otherwise. I would expect to have broken even (more or less) at the end of the run and the A/E value should be 1.0.

The calculation is simple enough, get the number of winners and then divide that by the expected number of winners. And that's it.

So, if in this example I had fifteen 'sixes' over the course of the 100 rolls then my calculation would be:
15 / (100/6)

The numerator is simply the number from the number of winners and the denominator is the expected number of winners from those 100 rolls. This then works out to be:
15 x 6 / 100 = 0.9

This shows that my fifteen winners were not the expected number as I had ended up with 90% of the expected number of winners when, ideally, I would be expecting sixteen or seventeen successful throws.

That's the basic theory and all it gives us is an idea of 'value', i.e. is this worth it? The bigger the number it is over 1.0 then the more value that it is, the lower the number below 1.0 the less value it is.