Statistics for Maintenance Modelling: Basic Probability Concepts

# Definition of Probability¤

When one talks of a probability, it is the probability of a particular event occurring that is of interest. One way of defining the probability of an event is in terms of its relative frequency.

Suppose that an experiment, with sample space S, is repeatedly performed under exactly the same conditions. For each event E of the sample space, we define n(E) to be the number of times in the first n repetitions of the experiment that the event E occurs. Then P(E), the probability of the event E, is defined by: