A Note on Variance

[mmbt0ne]

So apparently despite taking what must obviously be millions of bets over the course of a quarter the winning percentage of a casino can fluctuate by > 50%. This is crazy, and I never would've expected to see something like this.

WSJ blog link

Eventually they get around to saying their win percentage for table games fell to 14.7% in the third quarter of 2007, compared to 23.4% in the third quarter of last year, compared with an expected range of 20% to 22%