*Originally posted by BCShad0w*

In several books, I have seen a high pair v. low pair being a 4.5 to 1 and seeing that hitting a set it something like 8 in 1 to hit... Its driving me crazy to see where these figures have come form, and was wondering if someone knew where I could find where and how these odds are calculated, and if someone could help me understand where the professionals are getting these figures from.

Thanks. Chez.

I'll give you a example of hitting a set off the flop and hopefully you will get the jist of it.

There are 2 possible cards you can hit for your set. And we "know" four of the cards so there are 48 cards left. 2 of these you can hit, and so the probability of you hitting your set on any one card dealt is 2/48 or 1/24.

However you have 3 "chances" to hit this since there are 3 cards dealt on the flop so you're probability is 1/24 * 3 = 3/24 = 1/8

Therefore for you to be getting breakeven odds you need to get 7:1 because for the 7/8 times you don't hit there is a 1/8 time where you hit.

The books will quote 8:1 because this is what you need for calling on the odds to be +cEV - since you get better odds than the expected odds of you making your hand.

I don't know what you mean by high pair vs low pair unless you mean the odds of low pair winning when all in preflop - but this is a little bit more complicated since you have to account for the times where the low pair will hit set but highpair redraws out.