Studies of preverbal infants exposed to a bilingual environment have unveiled the existence of important similarities, but also significant differences in the way monolinguals-to-be and bilinguals-to-be solve the problem of language acquisition. In this paper, I review these studies and I argue that some apparent bilingual failures are the…

Studying human development involves describing, explaining, and optimizing intraindividual change and interindividual differences in such change and, as such, requires longitudinal research. The selection of the appropriate type of longitudinal design requires selecting the option that best addresses the theoretical questions asked about…

Argues that the status of the concept of equilibration is classified by considering Piagetian theory as a research program in the sense elaborated in 1974 by Lakatos. A pilot study was made to examine the precision and testability of equilibration in Piaget's 1977 model.(Author/RH)

Issues raised at an interdisciplinary conference on "Dialectics: a paradigm for the social sciences" are reviewed. The conference focused on the role of dialectical theory and methodology in designing and interpreting research in the social sciences. (BD)

An examination of the concept of external validity from two theoretical perspectives: a traditional mechanistic approach and a dialectical organismic approach. Examines the theoretical and methodological implications of these perspectives. (BD)

Problems in making inferences from a sample to a population and from one cohort to other cohorts are discussed. It is concluded that in most cases a longitudinal design using repeated measures is preferable to an independent samples design. (Author)

Five prototypic issues derived from a dialectical perspective are proposed: relationism, evolving reciprocity, probabilism, timing, and the nonequivalent temporal metric. It is argued that these issues, while not changing the scientific method, have implications for specific procedures. (Author)

Describes the use of simulated time sequences in the analysis of age-related and socio-historical changes in developmental research. (BD)

Presents a theoretical discussion of the role of cohort effects in the study of human development. The paper examines three problems associated with cohort analysis. These involve the interrelated problems of defining boundaries, defining distinctive experiences, and analyzing typical response patterns. (BD)

This article attempts to clarify the Schaie-Baltes controversy dealing with the formulation of adequate developmental research design. Crucial to clarification is distinguishing between description and explanation of developmental change. (MS)

Reviews examples from the recent psychological literature relating to object orientation and constancy. The conclusion is reached that the attempt to separate the constancy and discrimination questions in an experimental design employing only a single dependent variable fails practically and theoretically. A theoretically more acceptable…

Examines current conceptualizations of the mechanisms used to explain cognitive and social development and possible common mechanisms linking the two areas. Considers these mechanisms for both a mechanisric and the two areas. Considers these mechanisms from both a mechanistic and an organismic perspective. Presents a developmental model which…

This paper describes the design of the interdisciplinary study of the growth and development of Dutch children in progress at the University of Nymegen, The Netherlands. Schaie's design is based on a trifactorial model which isolates the contributions to developmental data of the factors age, cohort and time of measurement. (Author/MS)

Evaluates empirical studies on child development. Suggests that most such research consists of studies of a priori, nonempirical, logical relations between concepts, whose definitions guarantee the relationship studied. Argues that hypotheses are empirical if variables involved are semantically and logically independent. Research that is not based…

This paper represents a call for the rehabilitation and liberalization of the term learning. Preliminary steps for a revived theory of development and learning are described, including a consideration of such topics as compatibility or naturalness, accessibility and flexibility of learning, and processes of induction. Specific recommendations for…