Probability   The likelihood that a given event will occur. In statistics, probability is often expressed as a ratio of the number of actual occurrences of an event to the number of possible occurrences of the same event, i.e. there is a 50% probability of obtaining heads in a coin toss.

Used in the following modules: Data: Statistics, Data: Uncertainty, Error, and Confidence, Research Methods: Comparison, Research Methods: Experimentation, Research Methods: Modeling