Glossary term
Ogive: Meaning and Definition
Reviewed and approved by Dr. Anamika ShrivastavaPublished Last updated
An ogive is a graph of cumulative frequencies plotted against class limits. The less-than ogive rises from left to right using upper limits; the more-than ogive falls using lower limits. The two cross at the median, which can also be read by going across from half the total.
In more detail
An ogive is built from cumulative frequencies. Plot less-than frequencies against upper limits for a rising curve, and more-than frequencies against lower limits for a falling one. The point where they cross gives the median, and reading across from one-quarter or three-quarters of the total gives the quartiles.
Example
With cumulative frequencies 1, 10, 21, 29 and 30 at upper limits 4, 8, 12, 16 and 20, half of 30 is 15, and the ogive gives a median of about 9.8.
Key points
- Less-than ogive uses upper limits.
- More-than ogive uses lower limits.
- The two ogives intersect at the median.
Common mistake
Plotting cumulative frequency against class marks instead of class limits.
Related terms
Where it is explained
This term is explained in Class 11 Statistics Chapter 4: Presentation of Data.