Gambling Theory and Other Topics Standard deviation

[baztalkspoker]

I read over this fine book (the fifth edition btw) for the 1st time in a while last night as I was interested in checking out bankroll requirements from the mathematical point of view - I have a background in statistics though it's rusty, on page 47 Mason mentions about players willing to accept a 5% risk and says to use 1.64 standard deviations - at 1st I thought this was wrong because it was for a 90% confidence interval and that the risk was therefore 10% - then I knew it was unlikley that Mason would have got this wrong so thought about it some more and realised he was right of course as the 10% represents 5% error on the left hand side of the mean as well as 5% on the right and since it is the risk of ruin percentage we are interested in it's the left hand side of mean percentage that counts.

Anyway probably haven't explained this too well as just out of bed.

Just looking for confirmation that I have got this right and maybe others might also have been confused how Mason came up with this figure so thought I'd post on it to explain.

[Mason Malmuth]

Hi baztalkspoker:

You have it right. You're only interested in one tail since you don't object to being very lucky and winning much more than you're suppose to.

Best wishes,
Mason