activity
20242026
collaborators

8 papers

cs.LG2026

Lumberjack: Better Differentially Private Random Forests through Heavy Hitter Detection in Trees

Christian Janos Lebeda, David Erb, Tudor Cebere +1

Random forests are widely used in fields involving sensitive tabular data, but existing approaches to enforcing differential privacy (DP) typically degrade performance to the point…

cs.LG2026

Model Agnostic Differentially Private Causal Inference

Christian Janos Lebeda, Mathieu Even, Aurélien Bellet +1

Estimating causal effects from observational data is essential in fields such as medicine, economics and social sciences, where privacy concerns are paramount. We propose a general…

cs.DS2025

Weighted Fourier Factorizations: Optimal Gaussian Noise for Differentially Private Marginal and Product Queries

Christian Janos Lebeda, Aleksandar Nikolov, Haohua Tang

We revisit the task of releasing marginal queries under differential privacy with additive (correlated) Gaussian noise. We first give a construction for answering arbitrary workloa…

cs.CR2025

Avoiding Pitfalls for Privacy Accounting of Subsampled Mechanisms under Composition

Christian Janos Lebeda, Matthew Regehr, Gautam Kamath +1

We consider the problem of computing tight privacy guarantees for the composition of subsampled differentially private mechanisms. Recent algorithms can numerically compute the pri…

cs.CR2025

Better Gaussian Mechanism using Correlated Noise

Christian Janos Lebeda

We present a simple variant of the Gaussian mechanism for answering differentially private queries when the sensitivity space has a certain common structure. Our motivating problem…

cs.DS2025

Better Differentially Private Approximate Histograms and Heavy Hitters using the Misra-Gries Sketch

Christian Janos Lebeda, Jakub Tětek

We consider the problem of computing differentially private approximate histograms and heavy hitters in a stream of elements. In the non-private setting, this is often done using t…