Parameter - Parameter is a summary measure which describes or characterizes the entire population. A population may have many parameters, e.g. mean, median, variance, etc. Sample should be selected using a design consistent with sampling theory and implemented consistent with a statistically approved methodology. Statistic - Statistic is a summary measure which describes or characterizes a sample. Typically a statistic estimates a population parameter by applying the same, or similar, function that defines a parameter to a sample.
Statistic also is the numerical value that results when the function is applied to the sample.
Term Definition Descriptive Statistics Descriptive statistics are used to characterize or describe various features of the data. The average IQ of NJ college students is 125 and the average IQ of NY college students is 120. Descriptive Statistics - There are three primary categories of descriptive statistics which are discussed below. Central tendency describes tendency of numerical data to group or cluster about a central point. The population is then described in terms of this central point.