Empirical (Relative Frequency) Probability
In the definition of empirical (relative frequency) probability, empirical evidence is used as data for the sample space and the event outcomes of the experiment. If done properly, the probabilities deduced from the collected data may serve to predict future outcomes in the same situation.
Examples
Any experiment in which collected data from the past is used as the sample space involves the empirical definition of probability. Double-blind clinical trials for prescription drugs, monitoring of blood pressure in hospital patients, traffic reports of accidents in a particular city, weather reports for the amount of annual rainfall over a period of 25 years, and voting patterns across a country all involve statistical experiments whose outcomes were compiled from a process of collection of data that had been repeated over a period of time.
Empirical Probability of an Event
The nature of the outcomes in an experiment, in this case coming from a data set collected some time in the past, does not change the way the probability of an event E is calculated.
P(E) is still defined as:
# of E-outcomes # of elements in EP(E) = _________________ = _________________ .
total # outcomes # of elements in S
Last Updated by SAS October 07, 2026, 16:00:54
