activity
20202026
most citedImproving the utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates

29 citations · 129 across the 19 of their papers we have counts for

collaborators

23 papers

cs.LG2026

Choose Wisely and Privately: Proactive Client Selection for Fair and Efficient Federated Learning

Adda Akram Bendoukha, Heber Hwang Arcolezi, Nesrine Kaaniche +1

Federated Learning enables collaborative model training across decentralized data sources without data transfer. Averaging-based FL is limited by the presence of non-IID data, whic…

cs.CR2026

Beyond Epsilon: A Principled QIF Framework for Local Differential Privacy

Ramon G. Gonze, Natasha Fernandes, Heber H. Arcolezi +2

Local Differential Privacy (LDP) has become the de facto standard for privacy-preserving data collection in large-scale systems, in particular for the purpose of estimating frequen…

cs.CR2026

Understanding Disclosure Risk in Differential Privacy with Applications to Noise Calibration and Auditing (Extended Version)

Patricia Guerra-Balboa, Annika Sauer, Héber H. Arcolezi +1

Differential Privacy (DP) is widely adopted in data management systems to enable data sharing with formal disclosure guarantees. A central systems challenge is understanding how DP…

cs.CR2026

Estimating the True Distribution of Data Collected with Randomized Response

Carlos Antonio Pinzón, Ehab ElSalamouny, Lucas Massot +3

Randomized Response (RR) is a protocol designed to collect and analyze categorical data with local differential privacy guarantees. It has been used as a building block of mechanis…

cs.CR2025

Private Frequency Estimation Via Residue Number Systems

Héber H. Arcolezi

We present \textsf{ModularSubsetSelection} (MSS), a new algorithm for locally differentially private (LDP) frequency estimation. Given a universe of size and users, our $\v…

cs.CR2025

How Tough Is Location Anonymization? Re-identifying 100K Real-User Trajectories in Japan

Abhishek Kumar Mishra, Mathieu Cunche, Heber H. Arcolezi

Mobility traces are among the most revealing forms of personal data, yet trajectory releases are often protected only by ad hoc transformations. We stress-test such practices on re…

cs.LG2025★ 1 cited

Fair Play for Individuals, Foul Play for Groups? Auditing Anonymization's Impact on ML Fairness

Héber H. Arcolezi, Mina Alishahi, Adda-Akram Bendoukha +1

Machine learning (ML) algorithms are heavily based on the availability of training data, which, depending on the domain, often includes sensitive information about data providers.…

cs.CR2025

Revisiting Locally Differentially Private Protocols: Towards Better Trade-offs in Privacy, Utility, and Attack Resistance

Héber H. Arcolezi, Sébastien Gambs

Local Differential Privacy (LDP) offers strong privacy protection, especially in settings in which the server collecting the data is untrusted. However, designing LDP mechanisms th…

cs.CR2024★ 2 cited

Nob-MIAs: Non-biased Membership Inference Attacks Assessment on Large Language Models with Ex-Post Dataset Construction

Cédric Eichler, Nathan Champeil, Nicolas Anciaux +3

The rise of Large Language Models (LLMs) has triggered legal and ethical concerns, especially regarding the unauthorized use of copyrighted materials in their training datasets. Th…

cs.LG2024

A Systematic and Formal Study of the Impact of Local Differential Privacy on Fairness: Preliminary Results

Karima Makhlouf, Tamara Stefanovic, Heber H. Arcolezi +1

Machine learning (ML) algorithms rely primarily on the availability of training data, and, depending on the domain, these data may include sensitive information about the data prov…

cs.LG2023

On the Impact of Multi-dimensional Local Differential Privacy on Fairness

Karima Makhlouf, Heber H. Arcolezi, Sami Zhioua +2

Automated decision systems are increasingly used to make consequential decisions in people's lives. Due to the sensitivity of the manipulated data as well as the resulting decision…

cs.CR2023

Causal Discovery Under Local Privacy

Rūta Binkytė, Carlos Pinzón, Szilvia Lestyán +3

Differential privacy is a widely adopted framework designed to safeguard the sensitive information of data providers within a data set. It is based on the application of controlled…

cs.CR2023★ 6 cited

Revealing the True Cost of Locally Differentially Private Protocols: An Auditing Perspective

Héber H. Arcolezi, Sébastien Gambs

While the existing literature on Differential Privacy (DP) auditing predominantly focuses on the centralized model (e.g., in auditing the DP-SGD algorithm), we advocate for extendi…

cs.CR2023★ 2 cited

On the Utility Gain of Iterative Bayesian Update for Locally Differentially Private Mechanisms

Héber H. Arcolezi, Selene Cerna, Catuscia Palamidessi

This paper investigates the utility gain of using Iterative Bayesian Update (IBU) for private discrete distribution estimation using data obfuscated with Locally Differentially Pri…

cs.LG2023★ 10 cited

(Local) Differential Privacy has NO Disparate Impact on Fairness

Héber H. Arcolezi, Karima Makhlouf, Catuscia Palamidessi

In recent years, Local Differential Privacy (LDP), a robust privacy-preserving methodology, has gained widespread adoption in real-world applications. With LDP, users can perturb t…

cs.CR2022★ 1 cited

Frequency Estimation of Evolving Data Under Local Differential Privacy

Héber H. Arcolezi, Carlos Pinzón, Catuscia Palamidessi +1

Collecting and analyzing evolving longitudinal data has become a common practice. One possible approach to protect the users' privacy in this context is to use local differential p…

cs.CR2022★ 22 cited

On the Risks of Collecting Multidimensional Data Under Local Differential Privacy

Héber H. Arcolezi, Sébastien Gambs, Jean-François Couchot +1

The private collection of multiple statistics from a population is a fundamental statistical problem. One possible approach to realize this is to rely on the local model of differe…

cs.LG2022★ 10 cited

Differentially Private Multivariate Time Series Forecasting of Aggregated Human Mobility With Deep Learning: Input or Gradient Perturbation?

Héber H. Arcolezi, Jean-François Couchot, Denis Renaud +2

This paper investigates the problem of forecasting multivariate aggregated human mobility while preserving the privacy of the individuals concerned. Differential privacy, a state-o…

cs.CR2022★ 11 cited

Multi-Freq-LDPy: Multiple Frequency Estimation Under Local Differential Privacy in Python

Héber H. Arcolezi, Jean-François Couchot, Sébastien Gambs +2

This paper introduces the multi-freq-ldpy Python package for multiple frequency estimation under Local Differential Privacy (LDP) guarantees. LDP is a gold standard for achieving l…

cs.CR2022

Production of Categorical Data Verifying Differential Privacy: Conception and Applications to Machine Learning

Héber H. Arcolezi

Private and public organizations regularly collect and analyze digitalized data about their associates, volunteers, clients, etc. However, because most personal data are sensitive,…

cs.CR2021★ 29 cited

Improving the utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates

Héber H. Arcolezi, Jean-François Couchot, Bechara Al Bouna +1

This paper investigates the problem of collecting multidimensional data throughout time (i.e., longitudinal studies) for the fundamental task of frequency estimation under Local Di…

cs.CR2021★ 26 cited

Random Sampling Plus Fake Data: Multidimensional Frequency Estimates With Local Differential Privacy

Héber H. Arcolezi, Jean-François Couchot, Bechara Al Bouna +1

With local differential privacy (LDP), users can privatize their data and thus guarantee privacy properties before transmitting it to the server (a.k.a. the aggregator). One primar…

eess.SY2020★ 9 cited

RISE Controller Tuning and System Identification Through Machine Learning for Human Lower Limb Rehabilitation via Neuromuscular Electrical Stimulation

Héber H. Arcolezi, Willian R. B. M. Nunes, Rafael A. de Araujo +4

Neuromuscular electrical stimulation (NMES) has been effectively applied in many rehabilitation treatments of individuals with spinal cord injury (SCI). In this context, we introdu…