Two issues in analysis of interactions in complex linear models are considered. One is the omnibus test for interaction, and the other concerns follow-up tests when the omnibus test is significant. Reconsidered omnibus and follow-up tests are illustrated on an educational data set analyzed using the Statistical Analysis System. (SLD)

In August 1972, Kirkwood Community College began a research project to: (1) ascertain population and enrollment trends by various age groups for each of Iowa's 15 school areas and for the State as a whole; (2) ascertain potential enrollment by categories of students; (3) develop awareness of the relation of population and enrollment changes to…

This memorandum demonstrates a variance components methodology for partitioning the overall design effect (D) for a ratio mean into stratification (S), unequal weighting (W), and clustering (C) effects, so that D = WSC. In section 2, a sample selection scheme modeled after the National Longitudinal Study of the High School Class of 1972 (NKS)…

Seven studies were undertaken to further extend the development and testing of an academically-oriented preschool program for disadvantaged children. The studies investigated (1) Curricula Development and Testing in Bereiter-Engelmann Program, (2) Dual Kindergarten, (3) Follow-Up Data on the Achievement of Disadvantaged Children Who Participated…