The Census Tree is the largest-ever database of record links among the historical U.S. censuses, with over 700 million links for people living in the United States between 1850 and 1940. These high-quality links allow researchers in the social sciences and other disciplines to construct a...

Expansions of Medicaid eligibility intend to improve access to care, and to shift care from emergency rooms and inpatient hospital care to more appropriate sites. We examine the effect of Medicaid recipiency on the level and site of medical service utilization using data from 1985 and 1987...

This paper investigates the problem of responseand coding errors in the Current Population Survey. It draws upon a potentially rich source o finformation for verifying survey answers, a three month matched sample of CPS respondents, to analyze whether individuals' questionnaire responses...

Survey refusal in the Current Population Survey (CPS) has tripled over the last decade. This rise coincides with the emergence of rhetoric, largely from the political right, questioning the accuracy and integrity of government statistics. We examine how support for the Tea Party and the...

Linking individuals across historical datasets relies on information such as name and age that is both non-unique and prone to enumeration and transcription errors. These errors make it impossible to find the correct match with certainty. We suggest a fully automated method for linking...

This paper looks at the fertility and mortality experience of racial and ethnic groups in the United States from the early 20th century to the present. The first part consist of a description and critique of the racial and ethnic categories used in the federal census and in the published vital...

We discover and document errors in public use microdata samples ("PUMS files") of the 2000 Census, the 2003-2006 American Community Survey, and the 2004-2009 Current Population Survey. For women and men ages 65 and older, age- and sex-specific population estimates generated from the PUMS files...

The purpose of this paper is to help empirical economists think through when and how to weight the data used in estimation. We start by distinguishing two purposes of estimation: to estimate population descriptive statistics and to estimate causal effects. In the former type of research,...

Despite widespread concern about homelessness, fundamental questions about the size and characteristics of this hard to study population are unresolved, in large part because it is unclear whether existing data are sufficiently complete and reliable. We examine these questions as well as the...

A dynamic new field for health related technologies has emerged over the past decade. Many innovations aim at assisting elderly persons in monitoring and managing their personal health status. Other technologies support these persons in their activities of daily life, and make them feel safe and...