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THE MODE


In the previous posts, three measures of location have been discussed, namely the arithmetic mean, the median, and the quartiles. In this post, one more measure of location, the mode, will be discussed. Mode can be applied on data with any level of measurement.

If a group of data is given, its mode (denoted by Mo) is the data with the highest frequency of occurrence. In other words, the mode of a data set is the set member that appears most often.


Example 1
In a class, there are 30 and 10 male and female students, respectively. There are more men than women, so the mode of sex in the class is male.


Example 2
The following is a list of the favourite colours of some kindergarten students.



The mode of the favourite colours is red, because red appears most often.


Example 3
The following are 13 math test scores data of some junior high school students:
76   47   56   42   78   80   76   45   78   76   80   95   80
This data has two modes, namely (Mo)1 = 76 and (Mo)2 = 80. Both of these data appear 3 times (with a frequency of 3), while other data appear less than 3 times.

As Example 3 demonstrated, it is possible for a group of data to have more than one mode. The data in Example 3 is an example of bimodal data, which has two modes. If a group of data has only one mode, that data is called unimodal data. But if a group of data has more than two modes, the data is called multimodal data.

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