This user's manual describes the design, instrumentation, coding methodology, and special issues pertaining to the twin triad data file from the Early Childhood Longitudinal Study, Birth Cohort base year (9-month) data collection. Also included is information to help users access and use the...

This CD-ROM contains restricted-use base year (9-month data collection) twin triad data from the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B). The twin triad data file contains data from a subsample of twins videotaped with their mothers during a teaching interaction. Triadic...

Given the intensive demands that collecting attendance data places on program staff, it can often be challenging to collect and might result in a fair amount of missing data, which can compromise the reliability and validity of attendance estimates. Little is known about which methods for...

Household surveys are an important source of socioeconomic data and often yield important indicators to inform and monitor development policies. In developing countries, they have become an important form of data collection, supplementing or sometimes even replacing other data collection...

In this article the authors discuss and develop a statistical model that describes the relationship between an individual's short-term recall of his or her physical activity and usual activity over a long period of time. Modeling measurement error in recall data can be used to provide more...