How to Construct the table of frequency distributions

Frequency Distribution is a table that displays the frequency of various outcomes in a sample each entry in the table that contain the frequency or count of the occurences of valaues within a particular group or interval, and in this way, the table summarizes the distribution of values in the sample

A frequency distribution in statistics shows us a summarized grouping of data divided into mutually exclusive classes and the number of occurrences in a class. It is a way of showing unorganized data e.g. to show results of an election, income of people for a certain region, sales of a product within a certain period, student loan amounts of graduates, etc. Some of the graphs that can be used with frequency distributions are histograms, line charts, bar charts and pie charts. Frequency distributions are used for both qualitative and quantitative data.

Construction of frequency distributions :

1. Decide about the number of classes. The maximum number of classes 

    may be determined by Sturges formula:

K = 1+ 3,322 log  n

       whereas :

        K = Number of Class
        n = Number of observations in Data

2. Calculate the Range of Data

Range = ( Xmax - Xmin)

         X = Observation Value

      3. Decide width (Interval) of the class denote by ( I ) : 

For Example : 

If the total number of Observations is 50, the number of class (K) would be

K = 1+3,322 log n

K = 1+3,322 log (50)

K = 1+3,322 (1,69897)

K = 1+5,644

K = 6,644 or approximately by 7 is good