How The Average Can Lie

One of the things that researchers are often interested in is understanding what a‘typical’ or‘normal’ score on a particular test or measure looks like. For example, a lecturer might be curious to know how a typical student performs on the end of semester exam. Alternatively, a biologist might want to know how many offspring a particular species animal tends to have.

The most common measure of what constitutes a‘typical’ or‘normal’ score on a test or measure is the average or mean. To calcula...