Bias due to attrition of respondents poses a threat to the internal and external validity of research findings. Discusses methods of detecting attrition bias in longitudinal family research, and presents Heckman's procedure to correct attrition bias. Data from the University of California Longitudinal Study of Generations are used to illustrate…

Responds to a critique by Mudford, Hogg, and Roberts (1997) that raised concerns about the observation code used in a longitudinal research project to assess emerging behavior state patterns in young children with disabilities. Concerns about the thoroughness of the reliability data collected by Mudford are discussed. (Author/CR)

Global economic transformations have never been as dramatic as in the twentieth century. Most countries have experienced radical changes in the standards of income per capita, technology, fertility, mortality, income inequality and the extent of democracy in the course of the past century. It is the goal of many disciplines--economics, history,…

Researchers responsible for"Alcohol Abuse in Urban Indian Adolescents and Women: A Longitudinal Study for Assessment and Risk Evaluation" respond to critiques of the research project. Clarifies project goals, discusses issues related to longitudinal research, and addresses concerns related to research utilization and data publication.…

Critically reviews the influential study "Malnutrition and Environmental Enrichment" by Winick et al. (1975) and highlights what are considered to be statistical flaws in its analysis. Data in the classic study of height, weight, and IQ changes in three groups of adopted, malnourished Korean girls are reanalysed and conclusions…

Commentaries from 10 researchers concerning "Alcohol Abuse in Urban Indian Adolescents and Women: A Longitudinal Study for Assessment and Risk Evaluation" (R. Dale Walker and others). Reviewers commend the project for adding to the sparse longitudinal research on Indian peoples, while also pointing out problems and issues specific to…