Winner or a luckbox?

Winner or a luckbox?

Friday, 29 May 2009

Dear Dr Tom,

Because of the luck involved in poker it can be quite tricky to judge your own true abilities. I know I’m up at my local casino, but I’ve only been playing there four or five hours a night, two nights a week for a year. Is this enough to call myself a winning player, or could I still be a lucky payer? How many hands do you have to play before variance evens out? Does variance EVER even out?

Darren K., Edinburgh

Dear Darren,

Hmmm. Well, let’s see. That’s 100 sessions, assuming you don’t take time out for Christmas or other distractions. Twenty five hands per hour is about the best you can expect, so lets say 10,000 hands.

Now comes the maths. Assuming you’ve recorded the outcome from each session, do this. Find out how much you were up or down each session, square each outcome and add these squares all together. Then take away from this number your total profit (how much you’re up) squared, divided by the number of sessions. Then divide this number by the number of sessions minus 1. Take the result so far and square root it. Then divide it by the square root of the number of sessions. Multiply this number by 1.96 (’m not making all this up by the way). If you subtract this number from how much you’re up and then add it to how much you’re up you’ll get a range. There is a 95% chance that your real ability over the last year lies in this range. If the lower figure is negative – and after only 100 sessions it probably will be – you can’t be sure to a 95% degree of certainty that you are playing winning poker

If you don’t have records from each session, then basically the answer is that 10,000 hands gives you a pretty certain answer and 5,000 gives you a rough idea. So, yeah – assuming your profit is in the £0000’s, not £000’s, you’re almost certainly a winner.

Does variance ever even out? Theoretically, not completely, but what you get in the long run is never too far away from what you should be getting.

Dr Tom

Tags: Tom Sambrook, Strategy,