Zimmerman, D.W. (1985). Power functions of the t test and Mann-Whitney U test under violation of parametric assumptions. Perceptual and Motor Skills, 58, 891-896.
Zimmerman, D.W. (1986). Tests of significance of correlation coefficients in the absence of bivariate normal populations. Journal of Experimental Education, 54, 223-227.
Zimmerman, D.W. (1987). Comparative power of the Student t test and Mann-Whitney U test for unequal sample sizes and variances. Journal of Experimental Education, 55, 171-174.
Zimmerman, D.W., & Zumbo, B.D. (1989). A note on rank transformations and comparative power of the Student t test and Wilcoxon-Mann-Whitney test. Perceptual and Motor Skills, 68, 1139-1146.
Zimmerman, D.W., & Williams, R.H. (1989). Power comparisons of the Student t test and two approximations when variances and sample sizes are unequal. Journal of the Indian Society of Agricultural Statistics, 41, 206-217.
Zimmerman, D.W., & Zumbo, B.D. (1990). The effect of outliers on the relative power of parametric and nonparametric statistical tests. Perceptual and Motor Skills, 71, 339-349.
Zimmerman, D.W., & Zumbo, B.D. (1990). The relative power of the Wilcoxon-Mann-Whitney test and Student t test under simple bounded transformations. Journal of General Psychology, 117, 425-436.
Zumbo, B.D., & Zimmerman, D.W. (1991). Further evidence for Coren & Hakstian's "Methodological implications of interaural correlation: Count heads, not ears" and an alternative correction formula. Perception and Psychophysics, 50, 297-301.
Zimmerman, D.W. (1992). Failure of the Mann-Whitney test: A note on the simulation study of Gibbons and Chakraborti. Journal of Experimental Education, 60, 359-364.
Zimmerman, D.W., & Zumbo, B.D. (1992). Parametric alternatives to the Student t test under violation of normality and homogeneity of variance. Perceptual and Motor Skills, 74, 835-844.
Zimmerman, D.W., Williams, R.H., & Zumbo, B.D. (1992). Correction of the Student t statistic for nonindependence of sample observations. Perceptual and Motor Skills, 75, 1011-1020.
Zimmerman, D.W., & Zumbo, B.D. (1992). Increasing the power of tests of location and correlation by transforming scores to ranks and indicators. Journal of General Psychology, 119, 409-417.
Zimmerman, D.W., & Zumbo, B.D. (1992). Correction of ANOVA F tests for nonindependence of sample observations. Journal of Experimental Education, 60, 367-381.
Zimmerman, D.W. (1992). An extension of the rank transformation concept. Journal of Experimental Education, 61, 73-80.
Zimmerman, D.W. (1993). A note on nonindependence and nonparametric tests. Perceptual and Motor Skills, 76, 407-412.
Zimmerman, D.W., Williams, R.H., & Zumbo, B.D. (1993). Effect of nonindependence of sample observations on parametric and nonparametric statistical tests. Communications in Statistics: Simulation and Computation, 22, 779-789.
Zumbo, B.D., & Zimmerman, D.W. (1993). Symposium on alternatives to classical statistical procedures: Introduction to the symposium. Canadian Psychology, 34, 381-383.
Zumbo, B.D., & Zimmerman, D.W. (1993). Is the selection of statistical methods governed by level of measurement? Canadian Psychology, 34, 390-400.
Zumbo, B.D., & Zimmerman, D.W. (1993) Postscript: Some closing comments on "Alternatives to classical statistics (normal theory)." Canadian Psychology, 34, 440-445.
Zimmerman, D.W. (1993). Increasing the power of rank tests by reducing the number of ranks. Journal of Experimental Education, 61, 271-277.
Zimmerman, D.W., & Zumbo, B.D. (1993). Rank transformations and power of the Student t test and Welch t test for nonnormal populations with unequal variances. Canadian Journal of Experimental Psychology, 47, 523-539.
Zimmerman, D.W., & Zumbo, B.D. (1993). Relative power of the Wilcoxon test, the Friedman test, and repeated-measures ANOVA on ranks. Journal of Experimental Education, 62, 75-86.
Zimmerman, D.W., & Zumbo, B.D. (1993). A note on significance testing of correlation using scores, ranks, and modified ranks. Educational and Psychological Measurement, 53, 897-904.
Zimmerman, D.W. (1993). Mimicking properties of nonparametric rank tests using scores that are not ranks. Journal of General Psychology, 120, 509-516.
Zimmerman, D.W., & Williams, R.H. (1994). A note on robust tests for equal variances. Methodika, VII, 13-21.
Zimmerman, D.W. (1994). A note on the F test for equal variances under violation of random sampling. Journal of General Psychology, 121, 77-83.
Zimmerman, D.W. (1994). Simplified interaction tests for nonnormal data in psychological research. British Journal of Mathematical and Statistical Psychology, 47, 327-335.
Zimmerman, D.W. (1994). A note on modified rank correlation. Journal of Educational and Behavioral Statistics, 19, 357-362.
Zimmerman, D.W. (1994). A note on the influence of outliers on parametric and nonparametric tests. Journal of General Psychology, 121, 391-401.
Zimmerman, D.W. (1994). A note on the influence of distribution shape on nonparametric tests. Perceptual and Motor Skills, 79, 1160-1162.
Zimmerman, D.W. (1994). Increasing the power of the ANOVA F test for outlier-prone distributions by modified ranking methods. Journal of General Psychology, 122, 83-94.
Zimmerman, D.W. (1995). Increasing the power of nonparametric tests by detecting and downweighting outliers. Journal of Experimental Education, 64, 71-78.
Zimmerman, D.W. (1996). An efficient alternative to the Wilcoxon signed-ranks test for paired nonnormal data. Journal of General Psychology, 193, 29-40.
Zimmerman, D.W. (1996). A note on homogeneity of variance of scores and ranks. Journal of Experimental Education, 64, 351-362.
Zumbo, B.D., & Zimmerman, D.W. (1996). Comment on McKean & Vidmar, "A comparison of two rank-based methods for the analysis of linear models." The American Statistician, 50,198-199.
Zimmerman, D.W. (1996). Some properties of preliminary tests of equality of variances in the two-sample location problem. Journal of General Psychology, 123, 217-231.
Zimmerman, D.W. (1997). A note on interpretation of the paired-samples t test. Journal of Educational and Behavioral Statistics, 22, 349-360.
Zimmerman, D.W. (1998). Invalidation of parametric and nonparametric statistical tests by concurrent violation of two assumptions. Journal of Experimental Education, 67, 55-68.
Zimmerman, D.W. (2000). Statistical significance levels of nonparametric tests biased by heterogeneous variances of treatment groups. Journal of General Psychology, 127, 354-364.
Zimmerman, D.W. (2001). The effect of selection of samples for homogeneity on Type I error rates. Interstat.
Williams, R.H., Zumbo, B.D., & Zimmerman, D.W. (2001). The scientific contributions of R.A. Fisher. Edgeworth Series in Quantitative Educational and Social Science (Report No. ESQESS-2001-7). Vancouver, BC: University of British Columbia Edgeworth Laboratory for Quantitative Educational and Social Science.
Zimmerman, D.W. (2002). A warning about statistical significance tests performed on large samples of nonindependent observations. Perceptual and Motor Skills, 94, 259-263.
Williams, R.H., Zumbo, B.D., Ross, D., & Zimmerman, D.W. (2003). On the intellectual versatility of Karl Pearson. Human Nature Review, 3: 296-301.
Zimmerman, D.W., Zumbo, B.D., & Williams, R.H. (2003). Bias in estimation and hypothesis testing of correlation. Psicologica, 24, 133-158.
Zimmerman, D.W. (2003). A warning about the large-sample Wilcoxon-Mann-Whitney test. Understanding Statistics., 2, 267-280.
Zimmerman, D.W. (2004). Conditional probabilities of rejecting null hypotheses by pooled and separate variances t tests given heterogeneity of sample variances. Communications in Statistics—Simulation and Computation, 33, 69-81.
Zimmerman, D.W. (2004). Inflation of Type I error rates by unequal variances associated with parametric, nonparametric, and rank-transformation tests. Psicologica, 25, 103-133.
Zimmerman, D.W. (2004). A note on preliminary tests of equality of variances. British Journal of Mathematical and Statistical Psychology, 57, 173-181.
Zimmerman, D.W. (2004). Inflated statistical significance of Student's t test associated with small intersubject correlation. Journal of Statistical Computation and Simulation, 74, 691-696.
Zimmerman, D.W. (2005). Increasing power in paired-samples designs by correcting the Student t statistic for correlation. Interstat.
Zimmerman, D.W. (2006). Two separate effects of variance heterogeneity on the validity and power of significance tests of location. Statistical Methodology, 3, 341-394.
Zimmerman, D.W., & Zumbo, B.D. (2009). Hazards in choosing between pooled and separate-variances t tests. Psicologica, 30, 371-390.
Zimmerman, D.W. (2011). Inheritance of properties of normal and non-normal distributions after transformation of scores to ranks. Psicologica, 32, 65-85.
Zimmerman, D.W. (2011). Power comparisons of significance tests of location using scores, ranks, and modular ranks. British Journal of Mathematical and Statistical Psychology, 64, 233-243.
Zimmerman, D.W. (2011). A simple and effective decision rule for choosing a significance test to protect against non-normality. British Journal of Mathematical and Statistical Psychology, 64, 388-409.
Zimmerman, D.W. (2012). A note on consistency of nonparametric rank tests and related rank transformations. British Journal of Mathematical and Statistical Psychology, 65, 122-144.
Zimmerman, D.W. (2012). Correcting two-sample z and t tests for correlation: An alternative to one-sample tests on difference scores. Psicologica, 33, 391-418.
Zimmerman, D.W. (2013). Heterogeneity of variance and biased hypothesis tests. Journal of Applied Statistics, 40, 169-193.
Zimmerman, D.W. (in press). Robust significance testing and violation of three assumptions. Encyclopedia of Quality of Life Research.
Zimmerman, D.W. (in press). Consequences of choosing samples in hypothesis testing to ensure homogeneity of variance. British Journal of Mathematical and Statistical Psychology.
"Unfortunately, what is little recognized is that the most worthwhile scientific books are those in which the author clearly indicates what he does not know; for an author most hurts his readers by concealing difficulties."—Evariste Galois
"It is difficult to understand why statisticians commonly limit their inquiries to Averages, and do not revel in more comprehensive views. Their souls seem as dull to the charm of variety as that of the native of one of our flat English counties, whose retrospect of Switzerland was that, if its mountains could be thrown into its lakes, two nuisances would be got rid of at once."—Francis Galton
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