Quote: That is the correct risk of ruin formula. It does not assume that your hourly results are normally distributed. It is based on the assumption that the risk of ruin can be determined accurately based solely on your win rate and standard deviation. That is, the higher moments of the distribution can be ignored (the mean or win rate is related to the first moment, and the standard deviation is related to the second moment). This has been found to be a robust assumption for gambling games such as blackjack and poker. If you would really like to see a thorough analysis of this assumption, you could refer to this article, but this is for advanced and highly determined readers only. You can also refer to the thread that Robk linked to above for more of a hand waving discussion.
Thanks, it really had me thinking, especially because I could imagine two distributions with the same stddev and averages. But one with a lot of small losses, and one normally distributed. I felt (no mathametical proof though)that the small losses one had a bigger change of losing it all.
I haven't had the time (and i will need time ) to read the utah article, but i will as soon as possible. I've read the introduction and it indeed should tell me everything i want to know.
Thanks for taking the time to explain this to me, great post!