[[Actuarial Notes Wiki|Wiki]] / [[Actuarial Math]] / ==Probability Theory== > **Probability theory** is a branch of mathematics that studies the behavior of random phenomena. Probability theory is used for the following reasons: - to quantify uncertainty and - to predict the likelihood of outcomes in experiments or events. The probability of an event is a number between 0 and 1, where larger probabilities means an event is more likely to occur. Uncertainty about random phenomena is represented as a [[Concepts/Probability Distributions|probability distribution]] which assigns probabilities to all possible outcomes of an experiment. ## Read More 1. [[Assigning Probabilities]] 2. [[Foundational Mathematics of Probability]] ---