‘Expected Value (EV)’ Meaning | Casino & Gambling Terms Explained

Expected Value (EV) is a concept from probability theory used in gambling to determine the potential long-term return on a bet. It represents the average amount one can expect to win or lose per bet if the bet were to be repeated many times. EV is calculated by multiplying each possible outcome by the probability of that outcome occurring and then summing all those values.

Understanding Expected Value

• Mathematical Foundation: EV is the sum of all possible values each multiplied by the probability of its occurrence. It’s a prediction of the average outcome over a large number of instances.
• Positive and Negative EV: A positive EV (+EV) indicates a profitable long-term expectation, while a negative EV (-EV) suggests a loss over time.
• Relation to House Edge and RTP: EV is closely tied to the Return to Player (RTP) rate and the house edge. The house edge is essentially the negative expected value from the player’s perspective.

Calculating Expected Value

Simple Example: Consider a coin toss where you win $1 for heads and lose $1 for tails. The EV is calculated as:

• $$ EV = (0.5 \times 1) + (0.5 \times -1) = 0 $$.

This means, over time, you can expect to break even on this bet.

Complex Bets: For more complex bets, such as those in roulette or sports betting, the calculation involves all possible outcomes and their associated probabilities and payouts.

Importance of EV in Gambling

• Informed Decisions: Understanding EV helps gamblers make more informed decisions about which bets to place.
• Long-Term Perspective: While individual outcomes are unpredictable, EV provides a measure of what to expect over the long run.

Strategies Involving EV

• Seeking +EV: Skilled bettors look for +EV situations where the odds are in their favor, indicating a profitable opportunity over time.
• Avoiding -EV: Avoiding bets with a -EV reduces the likelihood of losing money in the long term.

EV in Different Casino Games

• Blackjack: Card counting strategies aim to identify +EV situations by keeping track of the cards played.
• Poker: Players calculate EV for different hands to decide when to call, raise, or fold.
• Sports Betting: Bettors compare their own perceived probabilities with those implied by the odds to find +EV bets.

Challenges with EV

• Variance: Short-term variance can make a +EV bet lose and a -EV bet win, which can be misleading.
• Emotional Factors: The psychological impact of wins and losses can affect a player’s ability to stick to +EV betting strategies.