Pronunciation: /ˈaʊt.laɪ.ər/ Explain

In statistics, an outlier is an observation that is numerically distant from the rest of the data. In many cases, outliers are excluded from the calculation of centers of the dataset or of the distribution. However, if any outlier is excluded, convention requires that the exclusion be noted with the calculations.

Click on the points and drag them to change the figure.

The red point is the outlier. The red line is the least fit lines including the outlier. The green line is the least squares line excluding the outlier. Click on the red point and drag it close to the other points. What happens to the red line?
Manipulative 1 - Outlier Created with GeoGebra.


  1. McAdams, David E.. All Math Words Dictionary, outlier. 2nd Classroom edition 20150108-4799968. pg 133. Life is a Story Problem LLC. January 8, 2015. Buy the book

Cite this article as:

McAdams, David E. Outlier. 12/21/2018. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/o/outlier.html.

Image Credits

Revision History

12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)
9/5/2018: Removed broken links, updated license, implemented new markup. (McAdams, David E.)
8/5/2010: Initial version. (McAdams, David E.)

All Math Words Encyclopedia is a service of Life is a Story Problem LLC.
Copyright © 2018 Life is a Story Problem LLC. All rights reserved.
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License