After reading the probability thread on coin flips I wanted to ask:

Last time I was in Vegas, I got a brilliant idea for playing roulette. Well not so brilliant.

#1: Its already been thought of. Its called the Martingale System.

#2: It didn’t work.

Basically, all the roulette tables have a little screen elevated on a pole which shows the results of the previous (20 or so) spins. Of course there are a ton of roulette tables near each other so I would look around for one that had a streak of about 5 or 6 reds or blacks in a row. Then I would throw down $10 on the opposite one next. If it didn’t work, I’d throw double that to cover my loss and make a profit.

Of course my thinking was that after already having had 6 reds in a row, its highly unlikely that there would be another 6. Of course what ended up happening is that the bet kept doubling and I didn’t have the money on hand to back it up. Big losses. Well anyway, I probably drank at least that much in free liquor.

Here’s the GQ: what’s wrong with my system of looking for already existing streaks. (Not the martingale system). I know that on each spin there’s a 50/50 chance REGARDLESS of previous spins. (lets just forget about 0 and 00 shall we?) But I also know that if stipulated from the beginning, the chance of 10 reds in a row is actually pretty low.

I’m having trouble wrapping my mind around exactly which one of these my case fits into.