IPUMS-International Privacy-Quality Balance in Restricted Access Census Samples 1 IPUMS-International High Precision Population Census Microdata Samples: Balancing the Privacy-Quality Tradeoff by Means of Restricted Access Extracts

Abstract. A breakthrough in the tradeoff between privacy and data quality has been achieved for restricted access to anonymized population census microdata samples. The IPUMS-International website, as of June 2007, offers to approved researchers integrated microdata for 26 countries (80 censuses), totaling more than 200 million person records. Samples for 60-80 additional censuses will be integrated over the next four years by the global collaboratory led by the Minnesota Population Center. Major funding is provided by the United States National Science Foundation and the National Institutes of Health. The statistical authorities of more than 70 countries have already entrusted microdata to the project under a uniform memorandum of understanding which permits researchers to obtain custom extracts without charge and to analyze the microdata using their own hardware and software. This paper describes the disclosure control methods used by the IPUMS initiative to protect privacy and to enhance quality in providing access to high precision census microdata samples