How do you calculate the house edge in a game of blackjack?

Incog

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The house edge in a game of blackjack is calculated using the formula: (probability of dealer winning - probability of player winning) * average bet size. For example, let's say that the player is playing a 6-deck game of blackjack with the following rules: dealer hits on soft 17, double after split allowed, no re-splitting aces, no surrender. The house edge for this game is around 0.5%. So the formula would be: (0.49 - 0.46) * $100 = $0.03.
 
The formula you provided is close, but there are a few corrections and clarifications to note when calculating the house edge in blackjack.

First, the probability of the dealer winning is not simply the inverse of the player winning probability. It takes into account the possibility of both the player and the dealer having certain hands that result in a push (tie).

To calculate the probabilities accurately, you would need to consider all possible outcomes based on the rules and the cards that have been dealt. This involves a complex analysis that many mathematicians and computer simulations have done to determine the exact probabilities for different blackjack rule variations.

Assuming you have access to these probabilities, you can use the formula: (probability of dealer winning - probability of player winning) * average bet size.

Let's use your example of a 6-deck game with the specified rules. If the probability of the dealer winning is 0.49 and the probability of the player winning is 0.46, and the average bet size is $100, then the calculation would be:

(0.49 - 0.46) * $100 = $3

So in this case, the house edge would be $3, not $0.03 as you initially mentioned.

It's important to note that the house edge is an average over the long run and doesn't guarantee any specific outcome for individual sessions. Additionally, this calculation assumes that the player is using the basic strategy, which is the mathematically optimal way to play every possible hand in blackjack.

Keep in mind that variations in rules, deck count, and specific strategies can have a significant impact on the house edge.
 
The calculation of the house edge in blackjack is quite complex and requires an understanding of statistics and probability theory. I'll try to simplify it for you, but please keep in mind that this is an approximation and not an exact calculation. There are two main factors that affect the house edge in blackjack: the number of decks being used and the rules of the game. The more decks that are used, the higher the house edge will be. And the rules of the game can also affect the house edge - for example, the house edge will be lower if the dealer has to hit on soft 17, and higher if the dealer has to stand on soft 17. To calculate the house edge, you need to first calculate the probability of each possible outcome in the game. For example, the probability of a player getting a blackjack is about 4.8%. The probability of a player winning with a hand other than blackjack is about 42%. The probability of the dealer getting a blackjack is about 8.3%. And the probability of the dealer winning with a hand other than blackjack is about 49.1%. Once you have all of these probabilities, you can then use them to calculate the house edge.

Alright, here we go. Let's say we're playing a game of blackjack with six decks, and the dealer must hit on soft 17. To calculate the house edge, we need to know the probability of each outcome and the payouts for each outcome.
To find the probability of each outcome, we'll use a binomial distribution, which is a way of modeling outcomes that have two possible results (win or lose). We'll calculate the probability of a win and the probability of a loss.
For example, let's say we're looking at the probability of getting a blackjack. There are 52 cards in a deck right, so there are two ways to get a blackjack: by getting an ace and a ten-value card (ace-ten, ace-jack, ace-queen, ace-king), or by getting an ace and a face card (ace-ace). The probability of getting a ten-value card on the first draw is 16/52, or 30.77%. The probability of getting a face card on the first draw is 12/52, or 23.07%. The probability of getting a blackjack is then the product of these two probabilities: 30.77% * 23.07%, which equals 7.
 
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