# Gambling Mathematics Glossary

While reading the pages on this site you may have come across a term which you were not familiar with. Below is a brief explanation of the most commonly referred-to terms that relate to the mathematics of gambling. Each term links to its own page that provides further information about each particular concept.

## Commonly used mathematical concepts in gambling:

The Combin Function is an Excel function that calls on combinatorial mathematics to provide a quick way of working out how many possible ways exist to form a combination in a given gambling scenario (for example, how many ways exist to form a combination of 6 numbers in a 49-ball lottery game)

How well a player can expect to do in a particular casino game over a series of fixed bets. This is calculated using both probability and the Combin Function, and is expressed as a percentage.

The erroneous belief in the escalating or declining probabilities for certain outcomes in games that involve independent events (for example, believing that throwing heads five times in a row means there’s a greater chance of throwing tails on the sixth throw, when actually, there isn’t).

This refers to the advantage that the casino has over a player in the long-term in any game based on a fixed bet. This is always above 0 but rarely exceeds 25%

Independent events have no bearing on future events, nor are they influenced be previous events (for example, throws of a coin). Dependent events exist in games like Blackjack.

Taking into account a number of mathematical variables in order to devise the optimum strategy for playing a particular casino game.

The theoretical percentage of a player’s funds that a machine or game at a casino will pay back to the player over time – typically varies between 85 and 98%

The Theory of Probability is a way of determining what the chances are of a certain event happening. It is a number between 0 and 1, or can be expressed as a percentage. 0 means the event is impossible, 1 means it is a certainty.