Correlation in Psychology

 

Correlation. The relationship between two variables. When two variables vary in a specific way with each other, they are said to covary. The covariation can be described in a graph of the relationship or in a summary statistic known as a correlation coefficient. There are a few common correlation coefficients.

Correlation coefficient. A statistic that summarizes a correlation between two variables. Correlations range from -1.0 to +1.0. Positive correlation values represent relationships such that as one variable increases, so does the other. Negative correlation values represent relationships that are inverse. In an inverse relationship, one value increases as the other value decreases. A common coefficient is the Pearson Product Moment Correlation Coefficient reported using a lower case, italicized letter r. See also correlation.