Statistics – Mode:

Along with mean and median, Mode is one of the central tendencies of data distribution. It does not involve much of tedious computations and can be found by easy observation of occurrences of data values. When data is tightly clustered around one or two values, Mode is the most meaningful average. Mode is the value that occurs most often. Because of the highest number of occurrence in the data set, Mode can be considered as the most typical value in the data set and hence a measure of central tendency.

Mode can be easily quoted by sheer counting or plotting the frequencies of each item. Mode is not affected by extreme values. The advantage of mode over the other two measures of central tendencies is it can be found for non numerical data sets.

The highest point of the relative frequency histogram corresponds to the mode of the data set. Always exactly one mean and one median exists for any data set. But not the mode because several different values could occur with the highest frequency. It may even happen that every value occurs with the same frequency; in such case the concept of the mode does not make much sense.

A data set with only one greatest frequency value is termed as Unimodal, while data sets which have the same greatest frequency for two values are called Bimodal. When the data set has more than two values occurring with the same greatest frequency, then the distribution is described as multimodal and each of such values is a mode.

When all the data values have the same frequency(occurring only once), then the data set is said to have no mode.

The class with highest frequency for grouped data with given frequencies is known as the modal class.

The mode for small data sets can be determined by plotting the occurrences on a number line.

Limitation of mode is it is not well defined, not based on all items and is affected by sampling fluctuations.

Example:

The following are points scored by a Basket ball team during the games played in a season.
94, 94, 95, 96, 97, 97, 97, 98, 98, 98, 98, 99, 100, 101, 102, 89, 90, 92, 92, 92, 93, 97, 97, 99, 99, 100, 103, 108.

The picture below shows the points marked for each occurrence of the score.

It can be seen that the point 97 has occurred 5 times in the season which is the highest.