Kenneth Land

Kenneth Carl Land (born August 19, 1942) is the John Franklin Crowell Professor Emeritus of Sociology at Duke University, where he is also a research professor at the Social Science Research Institute. He is also a fellow at the Center for the Study of Aging at Duke University Medical Center and a faculty fellow at the Duke University Center for Child and Family Policy.

Early life and education Land was born in Llano, Texas, on August 19, 1942. He received his Bachelor of Arts degrees in sociology and history from Texas Lutheran College in 1964, his Master of Arts degree in sociology from the University of Texas-Austin in 1966, and his Ph.D. in sociology and mathematics from the University of Texas-Austin in 1969. He then completed a one-year Social Science Research Council postdoc in mathematical statistics at Columbia University.

Career Land was a staff member of the Russell Sage Foundation for three years soon after completing his postdoc. At Russell Sage, he worked on the Indicators of Social Change project. From 1973 to 1977 he served the Mathematical Social Science Board, a National Science Foundation-funded body administered by the Center for Advanced Study in the Behavioral Sciences that organized research conferences on applications of mathematics in the social sciences. From 1976 to 1982, he was a member of the Social Science Research Council's Advisory and Planning Committee on Social Indicators, where he worked with F. Thomas Juster to coordinate a Workshop on Social Accounting Systems.

Research Land has done extensive research on contemporary social trends and quality-of-life measurement, demography, criminology, formal organizations, and mathematical and statistical models and methods for the study of social and demographic processes. Land worked on the Foundation for Child Development's Child and Youth Well-Being Index Project 1998 to 2017. In 2017, the YMCA OF THE USA began a joint sponsorship of the Annual Child and Youth Well-Being Index (CWI) Reports from this project.

Along with Raymond Teske and Hui Zheng, he has also researched capital punishment in Texas using monthly data on numbers of executions and homicides. This research found evidence of a short-term (within the month of an execution) deterrent effect on homicides that is concentrated among non-felony homicides and part of which is displaced to subsequent months.

Methodological contributions Beyond his substantive research, Land has contributed to the development and diffusion of quantitative methods in sociology. His 1969 chapter "Principles of Path Analysis", published in the inaugural volume of Sociological Methodology, was an early and widely cited treatment that helped introduce path analysis and causal modeling to sociologists.

With Daniel S. Nagin, Land co-authored "Age, Criminal Careers, and Population Heterogeneity" (1993), which specified nonparametric, mixed Poisson model for analyzing individual offending over the life course. The approach became a foundation for what is now known as group-based trajectory modeling, a technique used to identify distinct trajectories of behavior within a population.

With Yang Claire Yang, Land developed and popularized statistical applications of the intrinsic estimator as a means of addressing the identification problem in age period cohort (APC) accounting models, in which age, period, and cohort are linearly dependent. Their work, including a 2008 article in the American Journal of Sociology and the 2013 book Age-Period-Cohort Analysis: New Models, Methods, and Empirical Applications, has been applied in demography, epidemiology, and public health.

Honors and awards Land was elected a Fellow of the American Statistical Association 1978, the Sociological Research Association 1981, the American Association for the Advancement of Science 1992, ISQOLS 1997, and the American Society of Criminology 2004. His awards include the 1997 Paul F. Lazarsfeld Award from the Methodology Section of the American Sociological Association and ISQOLS' 2003 Distinguished Service Award.