A general model for recursive-nonrecursive causal networks of factors is outlined. The technical machinery required for operationalizing the model, in terms of analyzing empirical data, is indicated, and some of the more recent multivariate developmental theory is briefly noted in terms of the present model. (CS)

This paper attempts to clarify some of the changes that have taken place in developmental psychology between 1962 and 1975. Journal references in all articles in six journals devoted primarily to research in developmental psychology were tabulated. Patterns of references to developmental and to nondevelopmental journals are analyzed and discussed.…

Although the ability to conserve number held up well with age, quantity conservation performance was generally lower in the subjects over 65 years of age than in the college and adult age groups. (Author)

Argues that a better understanding of developmental processes is provided by three types of operant research -- laboratory behavioral descriptions, descriptions of naturalistic behavior-environment interdependencies, and predictive naturalistic studies. The usefulness of these processes are examined in light of the goals of life span developmental…