Spss Point Biserial Correlation. Binary variables are variables of nominal scale with only two values. Since the point biserial correlation is simply the special case of the pearson product moment correlation applied to a dichotomous and a continuous variable the coefficients produced by correlations are point biserial correlations when these types of variables are involved.
There is no special command in spss to calculate the point biserial correlation coefficient. It is a special case of the pearson s product moment correlation which is applied when you have two continuous variables whereas in this case one of the variables is measured on a dichotomous scale. This short video provides a brief description of point biserial correlation which is pearson s correlation between a dichotomous variable and a continuous v.
As described in the section on pearson s bivariate correlation in spss the first step is to draw the scatter diagram of both variables.
They are also called dichotomous variables or dummy variables in regression analysis. Simply run a correlations between your dichotomous and continuous variable. A point biserial correlation is used to measure the strength and direction of the association that exists between one continuous variable and one dichotomous variable. As described in the section on pearson s bivariate correlation in spss the first step is to draw the scatter diagram of both variables.
