Procedures for implementing random assignment with trickle processing and ways they can be corrupted are described. A computerized method for implementing random assignment with trickle processing is presented as a desirable alternative in many situations and a way of protecting against threats to assignment validity. (SLD)

Offers a critique on some of the papers on computers in science teaching that were presented at the 1985 National Association for Research in Science Teaching meeting. Implications for the conduct of research on computers in science learning are also suggested. (JN)

The substance of a commentary (SE 539 500) is a criticism of the over-generalizations by authors of computer-assisted instruction papers at the 1985 annual meeting of the National Association for Research in Science Teaching. This reaction attempts to examine the validity of the criticisms made in the commentary. (JN)

A computer-assisted analysis of studies on referential communication (giving directions/explanations) located 66 reports involving 80 experiments, 114 referential tasks, and over 6,200 individuals. The studies were entered into a statistical software package system (SPSS) and analyzed for characteristics of the subjects and experimental designs,…

Three and one-half years of research on computerized ability testing are summarized. The original objectives of the research were: (1) to develop and implement the stratified computer-based ability test; (2) to compare, on psychometric criteria, the various approaches to computer-based ability testing, including the stratified computerized test,…