Changes

1,058 bytes added ,  04:23, April 24, 2007
New page: {{statistics}} The '''Chi-square test''' is a statistical test that relies on the Chi-square distribution. The chi-square test is non-parametric and does not make as many assumptions ...
{{statistics}}

The '''Chi-square test''' is a statistical test that relies on the [[Chi-square distribution]]. The chi-square test is non-parametric and does not make as many assumptions about the data it is comparing. However, it has less statistical power because of this. The most common usage for the chi-square test is to compare [[statistical significance]] of the difference between proportions in data sets. This usually takes the form of a [[Bivariate tabular analysis]], or the intersections of proportional data of an [[independent variable]] and a [[dependent variable]].

For example, ones independent variable might be political affiliation and the dependent variable might be support for a particular law. In this hypothetical example the data looks like:

{|
|-
|
|Oppose
|Support
|-
|[[Liberal]]
|45
|5
|-
|[[Conservative]]
|10
|40
|-
|}

A chi-square test would be used to answer whether or not the difference between the relative proportions of support and opposition for the law compared to political affiliation was significant.
1,106

edits