Frequency table

Frequency of data occurs when we classify statistical data in respect of either a variable or an attribute. What is a frequency table may be defined as a tabular representation of statistical data, usually in an ascending order, relating to a measurable characteristic according to individual value or a group of values of the characteristic under study.

In case, the characteristic under study is an attribute, say nationality, and then the tabulation is made by allotting numerical figures to the different classes the attribute may belong like, in this Example of a Frequency Table or Frequency Table Example, counting the number of Americans, Indians, British, French, German and so on.  The qualitative characteristic is divided into a number of categories or classes in the frequency table which are mutually exclusive and exhaustive and the figures against all these classes are recorded. The figure corresponding to a particular class, signifying the number of times or how frequently a particular class occurs is known as the frequency of that class. Thus, the number of Americans, as found from the given data, signifies the frequency of Americans. So we define frequency table is a statistical table that distributes the total frequency to a number of classes.

A frequency table is useful in other statistical applications such as finding the frequency polygon, plotting a histogram, bar charts and pie charts. The frequency tables are used both for qualitative and quantitative data.

To manage and operate on a date that is put into a frequency table is much easier than operating on raw or unclassified data. The table can be used to calculate mean, median and mode. Which in turn are useful in coming to many business or scientific decisions.  Frequency tables also find application in the field of code cracking, science, marketing surveys, census surveys etc.

Testing of hypothesis is dependent on the similarities and differences between the frequency tables involved.  Frequency table is also useful in finding the standard deviations and other measures of central tendencies. A frequency table is said to be skewed when the mean and median are different. The study of this skewedness forms the basis of many important decisions in business and stock market.

If we have the test scores of 35 students from total score of 10, then we can make a frequency table of the data. The first column would be the score from 0,1, to 10 and the second column would be the number of students in each score. That would make it a simple frequency distribution.