Abstract
Grayson (see the preceding paper) discusses some circumstances in which estimates of genetic and environmental parameters derived from the study of twins reared together may be biased and documents in those circumstances what the magnitude of the biases may be. As Grayson suggests, the points he makes have been made previously by various authors and issues such as the power to detect dominance have been analyzed at some length. This paper draws attention to some other sources of variation which Grayson does not consider but which have been considered by other writers and which might have somewhat different consequences for the estimation of shared environmental effects. The classical twin study has never been an end in itself, but it is the nucleus of a systematic genetic approach to the study of human behavior.
References
Eaves, L. J. (1970).Aspects of Human Psychogenetics, Unpublished Ph.D. thesis, University of Birmingham, Birmingham.
Eaves, L. J. (1976). A model for sibling effects in man.Heredity,36:205–214.
Eaves, L. J. (1977). Inferring the causes of human variation.J. Roy. Stat. Soc. 140:324–355.
Eaves, L. J. (1978). Twins as a basis for the causal analysis of personality. In Nance, W. E. (ed.),Twin Research: Psychology and Methodology, Alan Liss, New York.
Eaves, L. J. (1979). The use of twins in the analysis of assortative mating.Heredity 43:399–409.
Eaves, L. J. (1988). Dominance alone is not enough.Behav. Genet. 18:27–33.
Eaves, L. J., Last, K., Young, P. A., and Martin, N. G. (1978). Model fitting approaches to the analysis of human behaviour.Heredity 41:249–320.
Fulker, D. W. (1979). Nature and nurture: Heredity. In Eysenck, H. J. (ed.),The Structure and Measurement of Intelligence, Springer-Verlag, Berlin.
Grayson, D. A. (1989). Twins reared together: Minimizing shared environmental effects.Behav. Genet. 19:593–604.
Heath, A. C. (1987). The analysis of marital interaction in cross-sectional twin data.Acta Med. Gemellol 31:41–49.
Heath, A. C., and Eaves, L. J. (1985). Resolving the effects of phenotype and social background on mate selection.Behav. Genet. 15:15–30.
Heath, A. C., Neale, M. C., Hewitt, J. K. Eaves, L. J., and Fulker, D. W. (1989). Testing structural equation models for twin data using LISREL.Behav. Genet. (in press).
hewitt, J. K. (1984). Normal components of personality variation.J. Personal. Soc. Psychol. 47:671–675.
Hewitt, J. K., Eaves, L. J., Neale, M. C., and Meyer, J. (1988). Resolving causes of longitudinal continuity or “tracking.” I. Longitudinal twin studies during growth.Behav. Genet. 18:133–152.
Jinks, J. L., and Fulker, D. W. (1970). Comparison of the biometrical genetical, MAVA and classical approaches to the analysis of human behavior.Psychol. Bull. 73:311–349.
Martin, N. G., Eaves, L. J., Kearsey, M. J., and Davies, P. (1978). The power of the classical twin study.Heredity 40:97–118.
Martin, N. G., Eaves, L. J., Heath, A. C., Jardine, R., Feingold, L., and Eysenck, H. J. (1986). The transmission of social attitudes.Proc. Natl. Acad. Sci. 83:4363–4368.
Neale, M. C., and Stevenson, J. (1989). Rater bias in the EASI temperament scales: A twin study.J. Personal Soc. Psychol. 56:446–455.
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Hewitt, J.K. Of biases and more in the study of twins reared together: A reply to grayson. Behav Genet 19, 605–608 (1989). https://doi.org/10.1007/BF01066257
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DOI: https://doi.org/10.1007/BF01066257