Standard deviation depends on bet made.Assuming player plays the house way, playing one on one against dealer, and half of bets made are as banker.Las Vegas single deck rules are dealer hits on soft 17, player may double on any two cards, player may not double after splitting, one card to split aces, no surrender.Liberal Vegas Strip rules: Dealer stands on soft 17, player may double on any two cards, player may double after splitting, resplit aces, late surrender.