Statistics and Probability Dictionary

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Probability

The probability of an event is a measure of the likelihood that the event will occur. Statisticians have agreed on the following rules and conventions.

  • The probability of any event can range from 0 to 1.
  • The sum of probabilities of all sample points in a sample space is equal to 1.
  • The probability of event A is the sum of the probabilities of all the sample points in event A.
  • The probability of event A is denoted by P(A).

Thus, if event A were very unlikely to occur, then P(A) would be close to 0. And if event A were very likely to occur, then P(A) would be close to 1.

See also:   Basic Probability | Probability | Probability Calculator