Department of Computer Science | Institute of Theoretical Computer Science | CADMO

Theory of Combinatorial Algorithms

Prof. Emo Welzl and Prof. Bernd Gärtner

Mittagsseminar (in cooperation with J. Lengler, A. Steger, and D. Steurer)

Mittagsseminar Talk Information

Date and Time: Friday, October 17, 2025, 03:00 pm

Duration: 30 minutes

Location: OAT S15 (15:00)

Speaker: Matt Regehr (University of Waterloo)

Query-Efficient Locally Private Hypothesis Selection via the Scheffe Graph

We propose an algorithm with improved query-complexity for the problem of hypothesis selection under local differential privacy constraints. Given a set of k probability distributions Q, we describe an algorithm that satisfies local differential privacy, performs ~O(k^3/2) non-adaptive queries to individuals who each have samples from a probability distribution p, and outputs a probability distribution from the set Q which is nearly the closest to p. Previous algorithms required either Ω(k^2) queries or many rounds of interactive queries. Technically, we introduce a new object we dub the Scheffé graph, which captures structure of the differences between distributions in Q, and may be of more broad interest for hypothesis selection tasks.


Upcoming talks     |     All previous talks     |     Talks by speaker     |     Upcoming talks in iCal format (beta version!)

Previous talks by year:   2025  2024  2023  2022  2021  2020  2019  2018  2017  2016  2015  2014  2013  2012  2011  2010  2009  2008  2007  2006  2005  2004  2003  2002  2001  2000  1999  1998  1997  1996  

Information for students and suggested topics for student talks


Automatic MiSe System Software Version 1.4803M   |   admin login