Analysis of Variance With Ipsative Measures

Measures with more than 1 score per participant, when the total for each participant equals the same constant, are said to be ipsative. Ipsativity occurs when data are percentages, with each participant's total equal to 100%, or when data are ranks, with each participant's total equal to t...

Full description

Saved in:
Bibliographic Details
Published in:Psychological methods 1997-06, Vol.2 (2), p.200-207
Main Authors: Greer, Tammy, Dunlap, William P
Format: Article
Language:English
Subjects:
Analysis
Analysis of Variance
Biological and medical sciences
Data analysis
Fundamental and applied biological sciences. Psychology
Human
Ipsative scales
Monte Carlo method
Psychology
Psychology. Psychoanalysis. Psychiatry
Psychology. Psychophysiology
Psychometrics. Statistics. Methodology
Repeated Measures
Statistical Data
Statistical Power
Statistics. Mathematics
Type I Errors
Variance
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Measures with more than 1 score per participant, when the total for each participant equals the same constant, are said to be ipsative. Ipsativity occurs when data are percentages, with each participant's total equal to 100%, or when data are ranks, with each participant's total equal to the sum of the ranks. When ipsative measures are analyzed with analysis of variance (ANOVA), certain sums of squares equal 0, and the average intercorrelation among measures is negative. These characteristics of ipsativity may result in violations of ANOVA assumptions, producing an inflated Type I error rate and affecting power. The purpose of this Monte Carlo study was to empirically examine the extent to which ANOVA is affected by ipsative data. Findings indicated that, with few exceptions, ANOVA worked quite well with ipsative data. Not only were Type I error rates well preserved, but power was nearly equivalent to that with nonipsative data.
ISSN:1082-989X
1939-1463
DOI:10.1037/1082-989X.2.2.200