How close is a coinflip?

[KJ o]

Is there a reasonably common definition of how close a hand must be for it to be referred to as a con-flip? 55/45? 60/40?

[cardcounter0]

It must be between 57.0765332% and 46.2900173%
Anything falling outside those bounds is using the term incorrectly.

Note: this is the accepted Geneva definition. The Chinese, the Koreans, and some parts of Finland still use the old Venice Definition.

[Wahoo91]

It must be between 57.0765332% and 46.2900173%
Anything falling outside those bounds is using the term incorrectly.

I think you know more about this than constructive receipt.

[2ndGoat]

So far you've received nothing but sarcasm from this question and in a sense you deserve it [img]/images/graemlins/wink.gif[/img] But in general I don't find people have a probability boundary for a coinflip but rather use it to describe a particular set of situations that usually run very close, by far the the most common being pocket pair vs two overcards before the flop. This can range from the overcards being ahead 54/46 with JTs vs 22, to the pair winning 57% of the time with QQ vs AKo. It also comes up with big draws on the flop like flush draw/gutshot vs one pair (~47/53), straight flush draw vs 2 pair, (~48/52) etc.

The numbers don't enter into it quite as much as does the type of situation you're facing. People usually won't call any kind of hand domination a coin flip even though it's possible in theory to find that situation at 50/40 pre-flop (A3o vs A2s) and yet it gets thrown around all the time at the 57/43 AKo vs QQ.

Another, perhaps more useful, definition of coin flip would be, "any heads-up configuration where the advantage of the favorite is sufficiently small that he/she probably shouldn't aim to get all-in in a tournament, if that player is one of the better in the field." As has been discussed many times before, in most such cases a great player will try to stay away from situations with huge variance and tiny expected value.

2ndGoat