chi-squared
UK[ˈkaɪ skweəd]US[ˈkaɪ skwɛrd]
adj
Relating to or involving a statistical method that uses the chi-squared distribution to assess how likely it is that any observed difference between sets of data arose by chance.
Morpheme Breakdown
chi
squared
chi
letter
squared
mathematical operation
Etymology
The term originates from the statistical test developed by Karl Pearson in 1900. It is named for the Greek letter chi (χ), which Pearson used to symbolize the test statistic. The 'squared' component refers to the core calculation of the method, which involves summing the squares of standardized differences between observed and expected data frequencies. Thus, the name literally describes the foundational operation performed on the chi-distributed statistic, evolving into the standard term for a fundamental tool in hypothesis testing.
Analysis
Structure: chi (letter) + squared (mathematical operation)
- chi: From the Greek letter chi (χ). In this context, it functions as a name for a specific statistical distribution and test.
- squared: From the verb 'square', meaning to multiply a number by itself. In this context, it indicates the mathematical operation of summing squared quantities.
Examples
The researcher used a chi-squared test to determine if the distribution of blood types was independent of geographic region.
A significant chi-squared value indicates that the observed results deviate substantially from the expected model.
The assumptions for applying the chi-squared test must be checked before interpreting the results.