Research designs that include planned missing data are gaining popularity in applied education research. These methods have traditionally relied on introducing missingness into data collections using the missing completely at random (MCAR) mechanism. This study assesses whether planned missingness can also be implemented when data are instead…

A weighted harmonic means analysis is presented that incorporates all of the available data, preserves the planned proportionality of the design, and avoids the problems associated with the replacement of missing data with sample estimates. (Author/BW)

Post-hoc blocking and analysis of covariance (ANCOVA) both employ a concomitant variable to increase statistical power relative to the completely randomized design. It is argued that the advantages attributed to the block design are not always valid and that there are circumstances when the ANCOVA would be preferred to post-hoc blocking.…

A methodology for determining the optimal number of observations to use in a measurement design when resource constraints are imposed is presented. Two- and three-facet designs are outlined. Parallel closed form formulae can easily be determined for other designs. (TJH)

Factor scale scores are sometimes used as weights to create composite variables representing the variables included in a factor analysis. If these composite variables are then used to predict some dependent variable, serious theoretical and methodological problems arise. This paper explores these problems and suggests strategies for circumventing…

This paper delineates conditions under which the use of change scores will not produce misleading results, and may perhaps be preferable to other methods of analysis. The validity of change scores in randomized pretest-posttest designs is discussed along with situations where analysis of change scores should be used. (Author/GK)

A method is presented for determining the optimal number of conditions to use in measurement designs when resource constraints are imposed. The method is illustrated using a multivariate two-facet design, and extensions to other designs are discussed. (SLD)

This article argues that the 1981 work of Carbno presented unwarranted conclusions because its design included an improper operationalization of the object of measurement, given the problems addressed, and because the sample sizes employed were too small. (Author/PN)

The purpose of this study was to determise the relative loss in statistical power of traditional methods of analysis when response-shift bias is present. Five methods of analysis (posttest scores only; postminus pretests; postminus retrospective pretest; postcovaried by pretest; postcovaried by retrospective pretest) were compared. (Author/BW)

The validity of various reliability-corrected procedures for adjusting for initial differences between groups in uncontrolled studies is established for subjects exhibiting linear fan-spread growth. The results are then extended to a nonlinear model of growth. (Author)

Factor analysis problems of scales with dichotomous items were illustrated using the Nowicki-Strickland Locus of Control Scale for Children. A different solution than that of R. E. Lindal and P. H. Venables (1983) was obtained, despite using similar samples--2 random samples of 671 and 674 male seventh and eighth graders. (SLD)