Joint relative frequency: It is found by dividing the frequency of a category (one not in the column total or row total) by the grand total.
Marginal relative frequency: It is found by diving a row total or a column total by the grand total.
Below we can find a table containing the information for a survey where a group of students selected a type of fruit (Explain 1, Example 1B).
Fruit
Gender
Apple
Banana
Orange
Total
Girl
16
10
14
40
Boy
25
13
14
52
Total
43
23
28
92
Now we can find the relative frequencies. Recall that these are obtained as the quotient between the frequency of each category and the total of all frequencies.
Fruit
Gender
Apple
Banana
Orange
Total
Girl
17.4 %
10.9 %
15.2 %
43.5 %
Boy
27.2 %
14.1 %
15.2 %
56.5 %
Total
44.6 %
25.0 %
30.4 %
100 %
We can check our relative frequency table by confirming that the sum of each row and column of joint relative frequencies equals the marginal relative frequencies at the end of the same row or column.
