Few would dispute the truth of the statement `People are Different', but there is much controversy over why. This book authoritatively explains the methods used to understand human variation, and extends them far beyond the primary `nature or nurture' question. After chapters on basic statistics, biometrical genetics, matrix algebra and path analysis, there is a state-of-the-art account of how to fit genetic models using the LISREL package. The authors explain not only the assumptions of the twin method, but how to test them. The elementary model is expanded to cover sex limitation, sibling interaction, multivariate and longitudinal data, observer ratings, and twin-family studies. Throughout, the methods are illustrated by applications to diverse areas such as obesity, major depression, alcohol comsumption, delinquency, allergies, and common fears.

Few would dispute the truth of the statement `People are Different', but there is much controversy over why. This book authoritatively explains the methods used to understand human variation, and extends them far beyond the primary `nature or nurture' question. After chapters on basic statistics, biometrical genetics, matrix algebra and path analysis, there is a state-of-the-art account of how to fit genetic models using the LISREL package. The authors explain not only the assumptions of the twin method, but how to test them. The elementary model is expanded to cover sex limitation, sibling interaction, multivariate and longitudinal data, observer ratings, and twin-family studies. Throughout, the methods are illustrated by applications to diverse areas such as obesity, major depression, alcohol comsumption, delinquency, allergies, and common fears.

What can social science, and demography in particular, reasonably expect to learn from biological information? There is increasing pressure for multipurpose household surveys to collect biological data along with the more familiar interviewer-respondent information. Given that recent technical developments have made it more feasible to collect biological information in non-clinical settings, those who fund, design, and analyze survey data need to think through the rationale and potential consequences. This is a concern that transcends national boundaries. Cells and Surveys addresses issues such as which biologic/genetic data should be collected in order to be most useful to a range of social scientists and whether amassing biological data has unintended side effects. The book also takes a look at the various ethical and legal concerns that such data collection entails.

Research today demands the application of sophisticated and powerful research tools. Fulfilling this need, The Oxford Handbook of Quantitative Methods is the complete tool box to deliver the most valid and generalizable answers to todays complex research questions. It is a one-stop source for learning and reviewing current best-practices in quantitative methods as practiced in the social, behavioral, and educational sciences. Comprising two volumes, this handbook covers a wealth of topics related to quantitative research methods. It begins with essential philosophical and ethical issues related to science and quantitative research. It then addresses core measurement topics before delving into the design of studies. Principal issues related to modern estimation and mathematical modeling are also detailed. Topics in the handbook then segway into the realm of statistical inference and modeling with chapters dedicated to classical approaches as well as modern latent variable approaches. Numerous chapters associated with longitudinal data and more specialized techniques round out this broad selection of topics. Comprehensive, authoritative, and user-friendly, this two-volume set will be an indispensable resource for serious researchers across the social, behavioral, and educational sciences.

This handbook provides research guidelines to study roles of the genes and other factors involved in a variety of complex behaviors. Utilizing methodologies and theories commonly used in behavior genetics, each chapter features an overview of the selected topic, current issues, as well as current and future research.

Twins as a Tool of Behavioral Genetics Edited by T. J. Bouchard, Jr. P. Propping Every human being is genetically unique and consequently genetically different from every other human being. The one exception is identical (monozygotic) twins, who share exactly the same genome. Fraternal (dizygotic) twins share half of their genes in common by descent. Twins of both types constitute "an experiment of nature". Because it is unethical to carry out powerful experiments on human beings in order to explore the causes of variation in human traits, this natural experiment with all of its vicissitudes is one of the few windows we have with which to view the genetic and environmental determinants of complex human behavioral traits. Many scientists believe that twins can only be used to estimate "heritability" and that they reveal nothing about how genes influence behavior. In addition, they argue that modern molecular genetics will quickly make twin research obsolete. These widely held views are largely incorrect. Twins are a unique and very powerful tool for exploring a wide variety of hypotheses about both the distal (mostly genetic) and proximal (mostly environmental) origins of human individual differences. Scientific knowledge accumulates most rapidly when scientists ask the right questions and utilize the right tools—the right tools for the job. This book attempts to highlight the questions that might be most productively addressed through the use of twin designs. Every tool, however, has its limitations. This book carefully examines the limitations and assumptions associated with the application of the method to each of the domains discussed. Goal of this Dahlem Workshop: to evaluate the environmental and genetic mechanisms underlying the structure and development of behavior in twins studies: the achievements, limitations, and potentials.

Twin Research: Biology, Health, Epigenetics, and Psychology is a comprehensive, applied resource in twinning and twin studies that is grounded in the most impactful findings from twin research in recent years. While targeted to undergraduate and graduate students, this compendium will prove a valuable resource for scholars already familiar with twin studies, as well as those coming to the field for the first time. Here, more than forty experts across an array of disciplines examine twinning and twin research methodologies from the perspectives of biology, medicine, genetic and epigenetic influences, and neuroscience. Chapters provide clear instruction in both basic and advanced research methods, family and parenting aspects of twinning, twin studies as applied across various disease areas and medical specialties, genetic and epigenetic determinants of differentiation, and academic, neurological and cognitive development. The presentation of existing studies and methods instruction empowers students and researchers to apply twin-based research and advance new studies across a range of biomedical and behavioral fields, highlighting current research trends and future directions. Offers unique insights into twinning rates, mechanisms and factors surrounding twinship Provides clear instruction on both basic and advanced twin research methods and study design Features leading international experts in twin biology, genetics, health and psychology Examines findings from recent twin studies across a broad array of health and behavioral studies