Wikipedia 10K Redux

Reconstructed by Reagle from Starling archive; see blog post for context.

Probability_Theory

:Probability

:Probability Axioms -- Probability Distributions

The basic theorems of probability can be developed easily from the Probability Axioms and [[Set Theory].

  • The sum of the probabilities for all the elementary events is one.
  • For any arbitrary events, A1 and A2, the probability of both events, Pr[A1*A2], is given by the sum of the probabilities of the elementary events in both A1 and A2. If the intersection is empty, then the probability is exactly zero.
  • For any arbitrary events, A1 and A2, the probability of either or both, Pr[A1+A2], is given by Pr[A1]+Pr[A2]-Pr[A1*A2]

    • The probability of some event happening knowning that some other one happened before can be computed using Conditional Probability.

    Dick Beldin