received honors from the Association of American Geographers in 1995 and was awarded the Victoria Medal by the Royal Geographical Society's Institute of British Geographers in 1996.

ROBERT M. BELL is a senior statistician and head of the statistics group at Rand. He has worked on many different projects, mainly in health and education. His primary areas of interest are survey design, survey analysis, and general experimental design issues. He received a B.S. in mathematics from Harvey Mudd College, an M.S. in statistics from the University of Chicago, and a Ph.D. in statistics from Stanford University.

GORDON J. BRACKSTONE is assistant chief statistician with responsibility for statistical methodology, computing, and classification systems at Statistics Canada. From 1982 to 1985 he was the director-general of the Methodology Branch of Statistics Canada. Previously, he was responsible for surveys and data acquisition in the Central Statistical Office of British Columbia. His professional work has been in survey methodology, particularly assessment of the quality of census and survey data. He is a fellow of the American Statistical Association and an elected member of the International Statistical Institute. He received B.Sc. and M.Sc. degrees in statistics from the London School of Economics.

MICHAEL L. COHEN, a senior program officer for the Committee on National Statistics, currently works with the Panel on Alternative Census Methodologies and the Panel on Estimates of Poverty for Small Geographic Areas and formerly served as study director of the committee's Panel on Statistical Methods for Testing and Evaluating Defense Systems. Previously, he was a mathematical statistician at the Energy Information Administration, an assistant professor in the School of Public Affairs at the University of Maryland, and a visiting lecturer at the Department of Statistics at Princeton University. His general area of research is the use of statistics in public policy, with particular interest in census undercount, model validation, and robust estimation. He received a B.S. in mathematics from the University of Michigan and an M.S. and a Ph.D. in statistics from Stanford University.

JOHN L. CZAJKA is a senior sociologist at Mathematica Policy Research, Inc. Much of his research has focused on statistical uses of administrative records, analysis of program participation, and the design and analysis of longitudinal data. This work has included designing strategies for handling incomplete data and addressing problems of nonsampling error in a number of contexts. During his many years of research with statistical data developed by the Internal Revenue Service, he prepared a study of