The authors empirically examined whether the validity of a residualized dependent variable after covariance adjustment is comparable to that of the original variable of interest. When variance of a dependent variable is removed as a result of one or more covariates, the residual variance may not reflect the same meaning. Using the pretest-posttest…

This study reports an empirical study of an explicit instruction of corpus-aided Business English collocations and verifies its effectiveness in improving learners' collocation awareness and learner autonomy, as a result of which is significant improvement of learners' collocation competence. An eight-week instruction in keywords' collocations,…

In order to provide an on-demand, open electrical engineering laboratory, we developed an innovative software-based Virtual Open Laboratory Teaching Assistant (VOLTA). This web-based virtual assistant provides laboratory instructions, equipment usage videos, circuit simulation assistance, and hardware implementation diagnostics. VOLTA allows…

Pretest-posttest experimental designs are often used in randomized control trials (RCTs) in the education field to improve the precision of the estimated treatment effects. For logistic reasons, however, pretest data are often collected after random assignment, so that including them in the analysis could bias the posttest impact estimates. Thus,…

High School seniors responded to two semantic differential instruments, containing dissimilar concepts purporting to measure the same variables, both before and after attending a college summer orientation program. Before-after component combinations were found to be highly similar. (Author/RC)

A pretest-posttest design for measuring the effects of educational programs uses comparison groups consisting of pupils like those in the treatment group but not getting that particular treatment. Although the design is geared primarily to evaluation of Title I programs in large cities, it should also apply to other situations. The plan for…

The purpose of this paper is to demonstrate the use of the general linear model (GLM) in problems with repeated measures on a dependent variable. Such problems include pretest-posttest designs, multitrial designs, and groups by trials designs. For each of these designs, a GLM analysis is demonstrated wherein full models are formed and restrictions…

A statistical method, Fishers Table of t (or t ratio), is used to determine the statistical significance of a comparison of results from pretests and post-tests of knowledge and skill taken by training program participants. A statistically significant improvement can demonstrate training effectiveness. (MS)

This paper describes the proposed Assessment Center at Mercy College in Dobbs Ferry, New York. The center is intended to provide statistical and technical support for the Mercy College elementary education, special education, and speech and hearing departments in the areas of student assessment, student guidance, and program evaluation. Evaluation…

Livingston's reliability coefficients and Harris' indices of efficiency were computed along with the classical internal consistency coefficients, KR-20's (Kuder-Richardson internal consistency coefficient), for 678 criterion-referenced tests in the A through E levels of an individualized mathematics program. The coefficients were carefully studied…

Conventional methods used for the presentation of pre- and post statistical information generally are deficient in economy and compactness and fail to show internal movement from pre- to posttest. This technique precludes these shortcomings through the presentation of information in a highly visible manner which reveals the strata of internal…

The pretest-posttest design referred to as Design 2 by Campbell and Stanley (1963) is commonly used in educational research and evaluation. The tenability of the assumption of a zero population difference commonly used with this design is questioned. A nonzero population estimate based on the mean difference observed in test-retest reliability…

A sizable representative subsample of the standardization group for the Metropolitan Achievement Tests participated in both the Fall and Spring standardization programs. Fall and Spring test records were matched for all such pupils and Fall-Spring "growth expectancies" were derived. Additionally, the sample was split into three subgroups…

The purpose of this Title III study was to compare the achievement and attitudes of ninth-grade algebra students who used programed texts with those of students who used conventional texts when the students were given a choice of varying degrees of classroom contact with the teacher. Following pre-unit tests of achievement and of attitudes toward…