A nonparametric method to analyze interactions: The adjusted rank transform test

Abstract Experimental social psychologists routinely rely on ANOVA to study interactions between factors even when the assumptions underlying the use of parametric tests are not met. Alternative nonparametric methods are often relatively difficult to conduct, have seldom been presented into detail in regular curriculum and have the reputation – sometimes incorrectly – of being less powerful than parametric tests. This article presents the adjusted rank transform test (ART); a nonparametric test, easy to conduct, having the advantage of being much more powerful than parametric tests when certain assumptions underlying the use of these tests are violated. To specify the conditions under which the adjusted rank transform test is superior to the usual parametric tests, results of a Monte Carlo simulation are presented.

[1]  Rand R. Wilcox,et al.  Testing Repeated Measures Hypotheses When Covariance Matrices are Heterogeneous: Revisiting the Robustness of the Welch-James Test Again , 2000 .

[2]  D. A. Kenny,et al.  Data analysis in social psychology. , 1998 .

[3]  S. Fiske,et al.  The Handbook of Social Psychology , 1935 .

[4]  James Friedrich,et al.  Statistical Training in Psychology: A National Survey and Commentary on Undergraduate Programs , 2000 .

[5]  Ronald Christensen,et al.  Log-Linear Models and Logistic Regression , 1997 .

[6]  P. Sen,et al.  Nonparametric methods in multivariate analysis , 1974 .

[7]  S. Sawilowsky,et al.  Analysis of Likert scale data in disability and medical rehabilitation research. , 1998 .

[8]  H. Keselman,et al.  Consequences of Assumption Violations Revisited: A Quantitative Review of Alternatives to the One-Way Analysis of Variance F Test , 1996 .

[9]  P. Sen,et al.  Nonparametric Methods in General Linear Models. , 1986 .

[10]  Thomas P. Hettmansperger,et al.  Statistical inference based on ranks , 1985 .

[11]  G. Box NON-NORMALITY AND TESTS ON VARIANCES , 1953 .

[12]  T. Lumley,et al.  The importance of the normality assumption in large public health data sets. , 2002, Annual review of public health.

[13]  G. W. Snedecor Statistical Methods , 1964 .

[14]  R. Iman,et al.  Rank Transformations as a Bridge between Parametric and Nonparametric Statistics , 1981 .

[15]  G. Keppel,et al.  Design and Analysis: A Researcher's Handbook , 1976 .

[16]  D. C. Howell Fundamental Statistics for the Behavioral Sciences , 1985 .

[17]  Ronald C. Serlin,et al.  QUANTITATIVE METHODS IN PSYCHOLOGY Comparison of ANOVA Alternatives Under Variance Heterogeneity and Specific Noncentrality Structures , 1986 .

[18]  R. Rosenthal,et al.  “Some Things You Learn Aren't So”: Cohen's Paradox, Asch's Paradigm, and the Interpretation of Interaction , 1995 .

[19]  Marti J. Anderson,et al.  A new method for non-parametric multivariate analysis of variance in ecology , 2001 .

[20]  Eugene F. Stone-Romero,et al.  Trends in Research Design and Data Analytic Strategies in Organizational Research , 1995 .

[21]  G. Glass,et al.  Consequences of Failure to Meet Assumptions Underlying the Fixed Effects Analyses of Variance and Covariance , 1972 .

[22]  Amy M. Buddie,et al.  Twenty Years of PSPB: Trends in Content, Design, and Analysis , 1999 .

[23]  Bruno D. Zumbo,et al.  Is the selection of statistical methods governed by level of measurement , 1993 .

[24]  S. Sawilowsky Nonparametric Tests of Interaction in Experimental Design , 1990 .

[25]  David J. Sheskin,et al.  Handbook of Parametric and Nonparametric Statistical Procedures , 1997 .