[pzhon]

[ QUOTE ]
I was messing with poker stove. I put AK vs. pairs, one pair at a time starting with 22 and going up to QQ. the higher the pair, the more equity it had against AK. Can someone explain why?

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That's not exactly true. Here are the values against AKo.

22: 52.649%
33: 53.375
44: 54.031
55: 54.617
66: 54.989
77: 54.984
88: 55.161
99: 55.271
TT: 56.877
JJ: 56.851
QQ: 56.758

Note the exceptions at 66->77, TT->JJ, and JJ->QQ.

Middle pairs do significantly better than low pairs primarily because they are counterfeited less frequently. They also win slightly more frequently when the board is a straight or a flush. I believe 66 does better than 77 by ruining the wheel for AK.

High pairs do better than middle pairs because they have more chances to make a straight when AK hits a pair or two, and they block AK from making a straight or have a chance to fill up. However, QQ is no better for this than TT, and TT can win with a few more low straights, which is more important than boards like QQJJx and AAQQT.