How to Calculate Class Interval

By Kiran Gaunle
...
Creatas/Creatas/Getty Images

Any data set accumulated for statistical purposes, such as the U.S. census, contains information that needs to be summarized and aggregated. It’d be impossible to list the attributes such as income and family size for each individual. Statisticians, therefore, use frequency distribution graphs to depict the data in a comprehensive manner, such as a histogram, which divides data into class intervals and counts the frequency at which all the members belonging to that class interval occur. Although there are no strict rules on how to calculate the size and number of class intervals, there are some conventional criteria that are useful.

About the Author

Kiran Gaunle is a freelancer based in New York. He started writing professionally in 2006. He has written research reports for the UN Development Programme and the "Kathmandu Post." Gaunle is working on a book of short stories and a novel. He holds a Master of Arts in international political economy and development from Fordham University.