There is really no way to look at one individual's play over a 50 year period to determine the chance that he might be a winner overall, with unknown variables in his play....prop bets, parlays, variation in bet size, amount of odds, etc. There is no way that anyone could use mathematics / probability to determine the "chance" that someone is lying about being a lifetime winner, because there is no way to know all the variables. The statement, "I'm a lifetime winner", or, "I make a living playing craps" will always remain a rhetorical declaration....a take it or leave it thing. And with the unknown variables, it would be difficult to even come close to computing the odds of the statements validity, or lack thereof. In your example, that would be about 5,000 hours of play, or 150,000 line decisions. But there is no way to know the number of betting decisions, come, place, lay, props, etc. Alan could take al of the exact variables, and come up with the "chance", but there will never be any "exact variables" provided. You can make up the variables, and run a simulation, but that is never reality, why bother. But having said that, one could plug in the most optimum betting strategy, and come up with those chances, Alan has already done that many times, and that does tell you that a less than optimum strategy diminishes the chance considerably, in most cases to the point one might say...."Ether you are a liar, or the luckiest SOB in the world.