Descriptive Statistics

Abstract

The mean is probably the most often used parameter or statistic used to describe the central tendency of a population or sample. When we are discussing a population of scores, the mean of the population is denoted with the Greek letter μ. When we are discussing the mean of a sample, we utilize the letter X with a bar above it. The sample mean is obtained as

$$ \overline{X}=\frac{{\sum\limits_{i=1}^n {{X_i}} }}{n} $$

(2.1)