What Does Outlier Mean?

An outlier, in mathematics, statistics and information technology, is a specific data point that falls outside the range of probability for a data set. In other words, the outlier is distinct from other surrounding data points in a particular way. Outlier analysis is extremely useful in various kinds of analytics and research, some of it related to technologies and IT systems.


Techopedia Explains Outlier

Outliers are common in many shapes and forms. For instance, an analysis of temperatures in an industrial process could yield hundreds of measurements within a range from 65 to 70 degrees, and one individual measurement of 140 degrees. In many cases, it is relatively easy to identify these outliers or black swan events from simple analysis.

Outliers can be useful in many types of projects and evaluations. Getting an outlier in a particular runtime test can show that there may be a bug in the system. Outliers in network security can represent potential threats to a network. In general, outliers represent unusual phenomena that can be evaluated and analyzed for a likely source or cause.


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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…