Texas Hold'em poker - How to rate starting hands

A two-card hand may be ranked according to the probability that it will prove to be the best hand after the widow is exposed. If the game is at a showdown, this probability can be estimated with precision.

A pair of aces (the best possible pair) would win x percent of the time, and a 7,2, unsuited (the worst possible couple since it is unsuited low cards, with no pair and no possibility for a straight) would win y percent of the time. x is more then 30%, and is much larger than y, which is under 3%.

However x is not 100%, and y is not zero. The point is this; any two card holding, by the time the whole widow is exposed, can be a sure winner.

Consider the worst holding, a 7,2 unsuited. The widow might contain three 7s, or three 2s, either of which would certainly give the owner of the 7,2 the lock hand. Or it might contain two 7s and a two, making 7,2 a highly probable winner. In actual play, the holding 7,2, unsuited, will prove to be a winner a much smaller percentage of the time than y because it will have been folded before the widow could have proved it to be a winner. Conversely, the holding ace, ace will win more than x percent of the time because many unpromising holdings that individually have a low probability of beating it will have been folded without giving the probabilities a chance to occur.