Using meta-analysis, randomized experiments in education that either clearly did or clearly did not experience student attrition were examined for the baseline comparability of groups. Results from 35 studies suggested that after attrition, the observed measures of baseline comparability of groups did not differ more than would be expected given…

The Prime Minister's Committee on Natural Science in Education in Great Britain reported in 1918 that "...in many schools more time is spent in laboratory work than the results obtained can justify." Seventy years later this conclusion can often still be drawn. This is particularly a problem in open distance education where laboratory practicals,…

The purpose of this study was to determine the concerns of Texas science teachers about the 40 percent laboratory time rule just prior to enforcement and at the end of its first year of implementation. The methodology, results of the first and second years, conclusions, and implications for teaching science are discussed. (KR)

This chapter examines the core analytic elements of randomized experiments for social research. Its goal is to provide a compact discussion for faculty members, graduate students, and applied researchers of the design and analysis of randomized experiments for measuring the impacts of social or educational interventions. Design issues considered…

Describes two new exercises in classical conditioning that use earthworms and houseflies. The animals are available year-round and pose no risk to the students or instructor. The conditioned stimuli are odorants. These elicit a conditioned response of contraction in worms or proboscis extension in flies. (MJP)

Discusses an analysis of the relationship of soil temperatures at 3 depths to various climatic variables along a 200-kilometer transect in west-central Oklahoma. Reports that temperature readings increased from east to west. Concludes that temperature variations were explained by a combination of spatial, temporal, and biophysical factors. (SG)

Describes the Tardigrada as a group of animals suitable for close study in project work. Gives reasons for their suitability and an illustrated identification key. Discusses possible investigations into the ecology and physiology of tardigrades. (Author/CW)

Discusses who has the right to determine the use of animals in scientific research which includes medical experimentation and the toxicity testing of compounds, ranging from pesticides to cosmetics. Provides a list of questions for consideration and discussion. (RT)

Describes the necking of polymer sheets that occurs when they are stretched. Discusses the effect and the mechanisms of necking. Lists four references. (YP)

Explains the characteristics and importance of random assignment in experimental research on education. Considers factors supporting causal inferences, the nature of "assignment units," differences between random sampling and random assignment, the characteristics of randomization tests, forms of random assignment, and effects of experimental…

Discusses the role of dogs in research, considering their use in studies related to: behavior; aging; anesthesia; gastrointestinal surgery; the brain; organ transplants; radiobiology; trauma and shock; arterial diseases; hemophelia; ophthalmology; diabetes; nutrition; cancer; lupus; cyclic neutropenia; thyroiditis; hepatitis; skeletal system,…

The approach of J. D. Sneed is used to argue for a distinction between theoretical and nontheoretical (or empirical) entities. Attention is directed toward this approach as an important facility for looking at statistics and for constructing a framework for the correct use of statistical theory in information retrieval experiments. (MBR)

Investigates strategies of 10-year-olds and 14-year-olds in tasks requiring prospective memory. Subjects were instructed to perform activities after waiting 30 minutes. As predicted, strategic time-monitoring occurred more frequently in the home than in the laboratory. Emphasizes the power of the laboratory as a contrasting context for…

The importance of targeting certain stages in the life cycle of the virus for antiviral therapy is discussed with reference to the Human Immunodeficiency Virus type 1. Research conducted on a core antigen, p24, is described. (MSE)

Criticizes an earlier essay that questioned the validity of contemporary educational research practices, especially those involving experimentation. Argues that research using experimentation is valid and can lead to new and generalizable knowledge. (FMW)