Expectation troubles

  • tkdkillermiller

    Expectation troubles

    I’m developing a simulator (which will be for public use when finished) where I’m able to select various rule sets. I’ve seen on the Wizard of Odds site that the expectation for the Aria 6-deck dealer stand on soft 17 game is 0.28% But in my simulator, the win rate is showing 48.0%, as opposed to 49.72% it should show to reflect a 0.28% house edge. After personally checking hundreds of hands one at a time, my simulator seems to be playing through all hands correctly.

    My questions:
    1) Are there other rules that could affect the expectation besides my input of: dealer hit/not hit soft17, DAS, RSA, #decks, cut-card penetration, late surrender yes/no, and number of splits allowed? (I also assume otherwise general rules such as BJ 3:2, double on any first 2 cards only, etc.)

    2) Is the expectation of 0.28% house edge correct for the rule set: dealer hits soft 17, DAS and RSA allowed, 6 decks, 70% penetration, late surrender allowed, and 4 splits allowed?

    Any and all help is appreciated!

  • KenSmith

     

    You really shouldn’t be using win probability to verify much of anything.
    In rough numbers, you’ll win about 44%, lose 48% and push 8% of the time using basic strategy. But, some of those wins and losses are multiple bets.
    The expected value is the real number you want to verify.

    Use the free combinatorial software available here for exact numbers to compare.

    Search the forums for more advice on likely bugs. One place to start looking is how you handle split Aces. One card only on each, and Ace-Ten after splitting is just 21, not blackjack.

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