Aims In this exciting era of gene discovery, we review evidence from family, adoption and
twin studies that examine the genetic basis for addiction. With a focus on the classical twin …

Examined developmental change in twin similarity with age contrasts in a meta-analysis of
twin studies from 1967 through 1985. Intraclass rs were coded from 103 papers that …

Presents an interactive theory of personality which assumes that there are inborn tendencies
that underlie individual differences in personality. 4 such dispositions (temperaments) are …

Consensus between self-ratings and stranger ratings of personality traits was investigated. A
sample of 100 adults was videotaped while entering and walking through a room, sitting …

Why are some people more sociable than others and some more emotionally sensitive?
What makes people differ from one another, and how do these differences come about …

The traditional twin method is predicated on the equal-environment assumption (EEA)—that
monozygotic (MZ) and dizygotic (DZ) twins are equally correlated in their exposure to …

In a recent article published in Criminology, Burt and Simons () claimed that the statistical
violations of the classical twin design render heritability studies useless. Claiming …

Model-fitting methods are now prominent in the analysis of human behavioural variation.
Various ways of specifying models have been proposed. These are identical in their …

The classic twin method is a simple and elegant natural experiment for examining ge ne tic
and environmental influences on behavior. The idea of using twins to study factors affecting …

Variance components estimates of political and social attitudes suggest a substantial level of
genetic influence, but the results have been challenged because they rely on data from …