We present three strategies to replace the null hypothesis statistical significance testing approach in psychological research: (1) visual representation of cognitive processes and predictions, (2) visual representation of data distributions and choice of the appropriate distribution for analysis, and (3) model comparison. The three strategies…

Consider the nonparametric regression model Y = m(X)+ [tau](X)[epsilon], where X and [epsilon] are independent random variables, [epsilon] has a median of zero and variance [sigma][squared], [tau] is some unknown function used to model heteroscedasticity, and m(X) is an unknown function reflecting some conditional measure of location associated…

Two statistics for use in the Shine-Bower single-subject analysis of variance designs are compared. Advantages and precautions concerning an alternate statistic to the mean square successive difference test for testing the slow change assumptions of the Shine-Bower error term are presented. (JKS)

While Spearman's rho and Kendall's tau are equally powerful rank-order correlation coefficients under conditions of normality, they have different metrics. Applied to the same data, tau is smaller in absolute value, often no more than two-thirds of the size of rho. This difference in correlational metric appears to need emphasis. (Author/CM)

To determine the effect of violating the assumption of homogeneity of covariance for the Tukey Wholly Significant Difference (WSD) test, Monte Carlo simulations varied the number of treatment groups, sample size, and degree of covariance heterogeneity. As covariance heterogeneity was increased, the empirical significance levels increased beyond…

Theta is a statistic which measures the degree to which a designated pattern successfully partitions a matrix of pre- and post-treatment ratings into regions typical of each of two treatments. In this paper, theta is extended to multivariate and multigroup cases. (Author/BW)

Social science researchers tend to analyze two dimensional frequency tables using Pearson's Chi-square test, which can be improved upon if the dependent variable represents an ordered qualitative characteristic. An improved modification by the Kruskal-Wallis analysis of variance on ranks is shown for a planned and post hoc analysis. (Author/CM)

The effects of some restraints not included in the classical assumptions of the F- and H-Test (e.g., correlation of mean and sample size) were examined in a simulation design. Also simulated was a situation in which two assumptions were not met simultaneously. (Author/BW)

An analytic procedure is presented which casts sequential moderator analysis in the role of a multivariate test of parallelism of regressions. The procedure addresses a test for comparing predictor-criterion relationships for one set of measurements or multiple predictors and repeated measurements on a criterion. (Author/PN)

Either Bartlett's chi-square test of sphericity or Steiger's chi-square test can be used to test the significance of a correlation matrix to determine the appropriateness of factor analysis. They were evaluated using computer-generated correlation matrices. Steiger's test is recommended due to its increased power and computational simplicity.…

Sampling experiments were used to assess the Type I error rates of the t test in situations where classes were randomly assigned to groups but analyses were carried out on individual student scores. Even small amounts of between-class variation caused large inflations in the Type I error rate of the t test. (Author/BW)