I overheard a comment that casinos like a hold of 10-12%.
When I was a blackjack dealer, the management always referred to "hold" meaning the amount of money the casino made, as a percentage of the amount of chips the player bought. It was a concept much different from the mathematical idea of expected value or return. For instance: a player goes to a blackjack table & buys $100 of chips. He plays 100 hands at $10 bet each, & at the end he cashes out for $90. The gambler will usually think in these terms: I had $1000 of action and lost $10, so I got a 99% return. But to the casino, the player bought in for $100 & the casino kept $10 of it, so the hold is 10%.
I don't know whether the casino uses a similarly unusual definition of "hold" for machines. But I'd guess that part of the confusion in discussing such things arises from misconceptions over how the casino uses the word "hold."
Stuart
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