This calculator allows you to measure the correlation between two variables in the special circumstance that one of your variables is dichotomous - that is, that it has only two possible values, 1 or 0 for the purposes of this calculator.

For example, you might want to know whether shoe is size is associated a baby's ice cream consumption. Shoe size would be the continuous variable (*X* below), and ice cream consumption the dichotomous variable (*Y* below), where 0 means it has never been consumed and 1 means it has been consumed on at least one occasion.

To use this calculator, just enter the values for your continuous variable into the first textbox (*X*), either one score per line or as a comma delimited list, and the values for your dichotomous variable, 1 or 0, into the second box (*Y*). Then hit "Calculate", and the calculator will spit out the value for *r*, plus details of the calculation.

No calculation has been performed yet.