Zimmerman (2014) suggested that our reanalysis adds little to the scientific literature. We disagree. We clarify our motivations and explain how further analyses based on his suggestion for age do not change our conclusions. Moreover, we believe the nascent experimental literature is more in line with our interpretations than Zimmerman's. We…

In this study, the authors tested the effects of Tekster [Texter], a comprehensive strategy-focused writing instruction program, using a switching replication design with three measurement occassions. The program was implemented by fourth, fifth, and sixth grade teachers (N = 76) in 60 general education classrooms in the Netherlands. Students (n =…

This addendum to previously published results presents alternative analyses of data from large-scale effectiveness studies of Cognitive Tutor Algebra I in middle schools and high schools. These alternative analyses produce results that are substantively the same as previously reported. We find a significant positive effect of 0.21 standard…

A meta-analysis by Tran, Sanchez, Arellano, and Swanson (2011) of the published RTI literature found that the magnitude of effect size (ES) between responders and low responders at posttest was significantly moderated by the pretest ES and the type of dependent measure administered, whereas no significant moderating effects were found in the mixed…

This article presents the authors' rejoinder to the comments of Howard Bloom, Derek Neal, and Mike Seltzer on their article. Their commentary focused foremost on the advantages and disadvantages of using Options A, B, or C in using instrumental variables in multisite trials. Of interest are the quantities one can estimate and test in each case,…

H. Bosch, F. Steinkamp, and E. Boller's (see record 2006-08436-001) meta-analysis, which demonstrated (a) a small but highly significant overall effect, (b) a small-study effect, and (c) extreme heterogeneity, has provoked widely differing responses. After considering D. B. Wilson and W. R. Shadish's (see record 2006-08436-002) and D. Radin, R.…

H. Bosch, F. Steinkamp, and E. Boller's (see record 2006-08436-001) review of the evidence for psychokinesis confirms many of the authors' earlier findings. The authors agree with Bosch et al. that existing studies provide statistical evidence for psychokinesis, that the evidence is generally of high methodological quality, and that effect sizes…

The H. Bosch, F. Steinkamp, and E. Boller (see record 2006-08436-001) meta-analysis reaches mixed and cautious conclusions about the possibility of psychokinesis. The authors argue that, for both methodological and philosophical reasons, it is nearly impossible to draw any conclusions from this body of research. The authors do not agree that any…

Spearman's "Law of Diminishing Returns" states that the g saturation of a test is greater for individuals with lower, rather than higher, test scores, and that it decreases with age. A common methodological problem in testing Spearman's "Law of Diminishing Returns" with respect to ability differentiation is how to create the…