Pub. date: 2007 | Online Pub. Date: September 25, 2007 | DOI: 10.4135/9781412952637 | Print ISBN: 9780761923879 | Online ISBN: 9781412952637| Publisher:Sage Publications, Inc.About this encyclopedia
Analysis of Variance
Katherine Y. Barnes
Analysis of variance (ANOVA) is a statistical procedure that attempts to determine the amount of variation in a variable y that is explained by a variable, or set of variables, X . It does so by decomposing a group of measurements into its components of systematic variation and random variation (or measurement error). A simple, one-way ANOVA compares the variation in a variable y within groups, to the variation between groups, where one defines the groups by a single variable. It is equivalent to a simple linear regression with indicator variables for each group. An ANOVA procedure estimates the following model: y = β X + e , where e is the random error term, y is the endogenous, or dependent, X ...