Arlene Sandra Ash is an American statistician who works on risk adjustment in health services. She is a professor of Quantitative Health Sciences in the University of Massachusetts Medical School, and chief of the Biostatistics and Health Services Research division there. Beyond health, Ash is also interested in electoral integrity, and has chaired the American Statistical Association Subcommittee on Electoral Integrity. She has also been involved in the anti-nuclear movement and has worked for equal pay for women.