"A Surprising Application of Differential Privacy"
Cynthia Dwork, Microsoft Research
Monday, December 8, 2014 at 12:00 Noon
Room 368 (CIT 3rd Floor)
A great deal of effort has been made to reduce the risk of spurious scientific discoveries, from the use of holdout sets and sophisticated cross-validation techniques, to procedures for controlling the false discovery rate in multiple hypothesis testing. However, there is a fundamental disconnect between the theoretical results and the practice of science: the theory assumes a fixed collection of hypotheses to be tested, or learning algorithms to be applied, selected non-adaptively before the data are gathered, whereas science is by definition an adaptive process, in which data are shared and re-used, and hypotheses and new studies are generated on the basis of data exploration and previous outcomes. Surprisingly, the challenges of adaptivity can be addressed using insights from differential privacy, a field of study supporting a definition of privacy tailored to private data analysis. As a corollary we show how to safely reuse a holdout set a great many times without undermining its power of "correctness protection," even when hypotheses and computations are chosen adaptively. Armed with this technique, the analyst is free to explore the data ad libitum, generating and evaluating hypotheses, verifying results on the holdout, and backtracking as needed.
Joint work with Vitaly Feldman, Moritz Hardt, Toni Pitassi, Omer Reingold, and Aaron Roth.
Cynthia Dwork, Distinguished Scientist at Microsoft Research, is renowned for placing privacy-preserving data analysis on a mathematically rigorous foundation. A cornerstone of this work is differential privacy, a strong privacy guarantee frequently permitting highly accurate data analysis. Dr. Dwork has also made seminal contributions in cryptography and distributed computing, and is a recipient of the Edsger W. Dijkstra Prize, recognizing some of her earliest work establishing the pillars on which every fault-tolerant system has been built for decades. She is a member of the National Academy of Sciences and the National Academy of Engineering, and a Fellow of the American Academy of Arts and Sciences.
Host: Ugur Cetintemel