Concept

Joint Relative Frequency

A joint relative frequency in a two-way frequency table is the ratio of a joint frequency and the total number of values or observations. As an example, the following data will be used.

		Hat preference
		Top hat	Beret
Gender	Male	$6$	$12$
Gender	Female	$15$	$20$

By adding all the joint frequencies, the total $53$ is found. The frequencies can now be divided by $53$ to find the joint relative frequencies.

		Hat preference
		Top hat	Beret
Gender	Male	$\frac{6}{5 3} \approx 0.11$	$\frac{1 2}{5 3} \approx 0.23$
Gender	Female	$\frac{1 5}{5 3} \approx 0.28$	$\frac{2 0}{5 3} \approx 0.38$

This table shows, for instance, that female's with a preference for berets make up about $38 %$ of the participants of the survey.