A Longitudinal Approach to ATI Research: Models for Individual Growth and Models for Individual Differences in Response to Intervention

This chapter provides a fresh look at the traditional statistical analyses in Aptitude-Treatment Interaction (ATI) research. Part I presents (a) statistical models for individual maturation in the outcome variable and (b) statistical models for individual differences in response to an intervention. In Part II simple combinations of these two kinds of models are used to evaluate the usefulness of the regression models commonly used in ATI research.