Question

what are the difficulties with reporting mode for interval/ ration variables?

Answer 1

Dear student, please comment in the case of any doubt and I would love to clarify it.  

When continuous or discrete variables are grouped in tables, the mode is defined as the class interval where most observations lie. This is called the modal-class interval.

In the example of the height of 50 Grade 10 girls, the modal-class interval would be 160 –< 165 cm, as this interval has the most observations in it.

The mode is rarely used as a measure of central tendency for numeric variables. However, for categorical variables, the mode is more useful because the mean and median do not make sense.

Next, you could determine the midrange of the modal class. The midrange is simply the midpoint between the highest and lowest values in a class. The mode is not used very often in conjunction with the midrange because it gives only a very poor estimate of the average.

The mode can be used with categorical data, but the mean and median cannot. The mode may or may not exist, and there may be more than one value for the mode.

Way to find mode for interval or ratio variable

When the data under consideration are grouped into class intervals, the mode can be determined by using a formula, but only if the classes are of equal width.

First, we identify the modal class. The modal class is defined as that class interval which has the highest frequency. Then we can calculate the mode using the following formula:

is the lower class boundary of the modal class.

is the frequency of the modal class.

is the frequency corresponding to the class next to the modal class.

is the frequency of the class previous to the modal class.

is the equal class width.