#### Answer

A parameter is a numerical description of a population characteristic.
A statistic is a numerical description of a sample characteristic.

#### Work Step by Step

Data sets all have characteristics and usually we would like to investigate a specific characteristic. It is important to distinguish between the characteristics of a population and that of a sample, because they can differ.
A parameter is therefore a numerical description of a population characteristic.And, a statistic is a numerical description of a sample characteristic.
It is important to note that a sample statistic can differ from sample to sample whereas a population parameter is constant for a population.