Longitudinal and Time-Lab Designs in Educational Research: An Alternate Sampling Model

Abstract

The basic premise of this paper is that educational researchers have relied too heavily on research designs that lack sensitivity either when used for the purposes of explicating the short-term (e.g., within-grade) influences of educational experiences or for describing the long-term and cumulative influences of schooling. This paper examines an alternate sampling model that focuses on the assessment of the effects of educational experiences and the description of behavior that changes both within and across grades as a function of schooling. Many of the inferences of this paper rest on the assumption that educational research, like developmental research, can be described by problems which take the form: