This is the technical report for Wave 7 of the Study of Early Education and Development (SEED), a major longitudinal study following nearly 6,000 children from across England from age 2. Wave 7 included a face-to-face survey of families and children in 2022-2023, when children were in year 6 at school and aged 10-11 years old. For SEED wave 7, the…

Most study samples show less variability in key variables than do their source populations due most often to indirect selection into study participation associated with a wide range of personal and circumstantial characteristics. Formulas exist to correct the distortions of population-level correlations created. Formula accuracy has been tested…

The Programme for the International Assessment of Adult Competencies (PIAAC) has been planned as an ongoing program of assessment. The first cycle of the assessment has involved two "rounds." The first round, which is covered by this report, took place over the period of January 2008-October 2013. The main features of the first cycle of…

This report is structured so as to provide technical detail about each aspect of International Civic and Citizenship Education Study (ICCS). The overview is followed by a series of chapters that provide detail about different aspects of ICCS. Chapters, 2, 3, 4, and 5 are concerned with the instruments. Chapter 2 provides information about the…

This study investigated the possibility that apparent sex differences in IQ are at least partly created by the degree of sample restriction from the baseline population. We used a nationally representative sample, the 1970 British Cohort Study. Sample sizes varied from 6518 to 11,389 between data-collection sweeps. Principal components analysis of…

The Programme for International Assessment of Adult Competencies (PIAAC) will establish technical standards and guidelines to ensure that the survey design and implementation processes of PIAAC yield high-quality and internationally comparable data. This document provides a revised version of the technical standards and guidelines originally…

The Early Childhood Longitudinal Study (ECLS) is a new study that will focus on children's early school experiences beginning in kindergarten. Approximately 23,000 children will be selected as they enter kindergarten and followed through fifth grade. Base-year data will be collected in the fall of 1998, but there will a field test in the 1996-97…