title: Interpretation of research data: analysis of variance.
abstract: The use of analysis of variance (ANOVA) in research studies is discussed. ANOVA is a set of procedures used in testing for differences between means that partitions the total variation found in a sample of score values into "explained" and "error" components. The test statistic used in ANOVA is the F ratio, and probabilities are found in tables of F distributions similar to t, z, or x2 tables. Equations used in ANOVA procedures and exercises for computational practice are given. Design of experiments that facilitate ANOVA use is discussed, as is the difference between t tests and F tests. Total sum of squares, mean squares, and squared correlation ratio are described.
mesh_terms: D000704:Analysis of Variance; D003365:Costs and Cost Analysis; D011307:Drug Prescriptions / Q000191:economics; D008722:Methods; D011897:Random Allocation; D013810:Therapeutic Equivalency