Probability

Probability is the measure of the likelihood that an event will occur.

Description

Probability is quantified as a number between 0 and 1 (where 0 indicates impossibility[2] and 1 indicates certainty).

The higher the probability of an event, the more certain that the event will occur.

A simple example is the tossing of a fair (unbiased) coin. Since the coin is unbiased, the two outcomes ("head" and "tail") are both equally probable; the probability of "head" equals the probability of "tail." Since no other outcomes are possible, the probability is 1/2 (or 50%), of either "head" or "tail". In other words, the probability of "head" is 1 out of 2 outcomes and the probability of "tail" is also 1 out of 2 outcomes, expressed as 0.5 when converted to decimal, with the above-mentioned quantification system. This type of probability is also called a priori probability.

These concepts have been given an axiomatic mathematical formalization in probability theory, which is used widely in such areas of study as mathematics, statistics, finance, gambling, science (in particular physics), artificial intelligence, machine learning, computer science, game theory, and philosophy to, for example, draw inferences about the expected frequency of events.

Probability theory is also used to describe the underlying mechanics and regularities of complex systems.

See also

• Chance (disambiguation)
• Class membership probabilities
• Equiprobability
• Heuristics in judgment and decision-making
• Probability theory
• Statistics
• Estimators
• Estimation Theory
• Probability density function

External links

• Probability @ Wikipedia