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)

The concepts of quantitative and structural change are considered from a multivariate perspective. A hybrid of these two types of change, quantistructural change, is described. (CS)

A general developmental model for interindividual differences, intraindividual differences, and intraindividual changes is described in terms of individuals, variables, and occasions. (ST)

Presents: (1) an outline of prototype age-related changes in cognitive structure; (2) an application of these interrelationships to some existent research and concepts in the abilities domain; and (3) a discussion of the multifactor approach in structuring age-related change to organismic views of cognitive development. (SDH)

ANOVA designs are used for description and/or explanation of developmental phenomena. These consist of taking any two of age, cohort, or time of measurement as independent variables. Employment of ANOVA has led researchers down blind alleys. Regression techniques are more useful. (Author)