CV

Education

• PhD Computer Science (expected 2024), Graz University of Technology
  Thesis: User Privacy in Recommender Systems
• Dipl.-Ing. (MSc.) Computer Science (with distinction, 2019), Graz University of Technology
  Thesis: Studying Non-mainstream Music Listening Behavior for Fair Music Recommendations
• BSc. Computer Science (2016), Graz University of Technology
  Thesis: A Toolkit for activity-based Analysis of Learning Groups within a Social Network

Work Experience

• since 01/2020, Researcher, Privacy in Recommender Systems (Know-Center GmbH, Graz, Austria)
• 04/2019-12/2019, Junior Researcher, Context-aware Recommender Systems (Know-Center GmbH, Graz, Austria)

Publications

Establishing and evaluating trustworthy AI: overview and research challenges

Kowald D, Scher S, Pammer-Schindler V, Müllner P, Waxnegger K, Demelius L, Fessl A, Toller M, Mendoza Estrada IG, Šimić I, Sabol V, Trügler A, Veas E, Kern R, Nad T and Kopeinik S (2024) Establishing and evaluating trustworthy AI: overview and research challenges. Front. Big Data 7:1467222. doi: 10.3389/fdata.2024.1467222

AI-Powered Immersive Assistance for Interactive Task Execution in Industrial Environments

Making Alice Appear Like Bob: A Probabilistic Preference Obfuscation Method For Implicit Feedback Recommendation Models

Escobedo, G. et al. (2024). Making Alice Appear Like Bob: A Probabilistic Preference Obfuscation Method For Implicit Feedback Recommendation Models. In: Machine Learning and Knowledge Discovery in Databases. Research Track. ECML PKDD 2024.

The Impact of Differential Privacy on Recommendation Accuracy and Popularity Bias

Müllner, P., Lex, E. Schedl, M., Kowald D. (2024). The Impact of Differential Privacy on Recommendation Accuracy amd Popularity Bias. In Advances in Information Retrieval: 46th European Conference on Information Retrieval, ECIR 2024, Glasgow, UK, March 24–March 28, 2024, Proceedings, Part IV (pp. 483-484). Cham: Springer Nature Switzerland.

Differential privacy in collaborative filtering recommender systems: a review

Müllner, P., Lex, E., Schedl, M., Kowald, D. (2023). Differential privacy in collaborative filtering recommender systems: a review. In Frontiers in Big Data 6 (2023).

ReuseKNN: Neighborhood Reuse for Differentially Private KNN-Based Recommendations

Muellner, P., Lex, E., Schedl, M., Kowald D. ReuseKNN: Neighborhood Reuse for Differentially Private KNN-Based Recommendations. ACM Trans. Intell. Syst. Technol. 14, 5, Article 80, 29 Pages. (2023). https://doi.org/10.1145/3608481

User Privacy in Recommender Systems

Müllner, P. (2023). User Privacy in Recommender Systems. In Advances in Information Retrieval: 45th European Conference on Information Retrieval, ECIR 2023, Dublin, Ireland, April 2–6, 2023, Proceedings, Part III (pp. 456-461). Cham: Springer Nature Switzerland.

Towards employing recommender systems for supporting data and algorithm sharing

Peter Müllner, Stefan Schmerda, Dieter Theiler, Stefanie Lindstaedt, and Dominik Kowald. 2022. Towards employing recommender systems for supporting data and algorithm sharing. In Proceedings of the 1st International Workshop on Data Economy (DE 2022). Association for Computing Machinery, New York, NY, USA, 8–14. https://doi.org/10.1145/3565011.3569055

Position Paper on Simulating Privacy Dynamics in Recommender Systems

Müllner, P., Lex, E., & Kowald, D. (2021). Position Paper on Simulating Privacy Dynamics in Recommender Systems. arXiv preprint arXiv:2109.06473.

Support the underground: characteristics of beyond-mainstream music listeners

Kowald, D., Muellner, P., Zangerle, E. et al. Support the underground: characteristics of beyond-mainstream music listeners. EPJ Data Sci. 10, 14 (2021). https://doi.org/10.1140/epjds/s13688-021-00268-9

Robustness of Meta Matrix Factorization Against Strict Privacy Constraints

Muellner, P., Kowald, D., & Lex, E. (2021). Robustness of meta matrix factorization against strict privacy constraints. In Advances in Information Retrieval: 43rd European Conference on IR Research, ECIR 2021, Virtual Event, March 28–April 1, 2021, Proceedings, Part II 43 (pp. 107-119). Springer International Publishing.

Talks

The Impact of Differential Privacy on Recommendation Accuracy and Popularity Bias

March 28, 2024

at 46rd European Conference on IR Research (ECIR) 2024, Glasgow

User Privacy in Recommender Systems

April 02, 2023

at 45th European Conference on Information Retrieval (ECIR) 2023, Dublin, Ireland

Towards Employing Recommender Systems for Supporting Data and Algorithm Sharing

December 08, 2022

at DataEconomy (DE) Workshop at the International Conference on emerging Networking EXperiments and Technologies (CoNEXT) 2022, Online

Impact of Meta Learning for Privacy-Preserving Recommender System

December 06, 2021

at The Responsible AI Forum (TRAIF) 2021, Online

Robustness of Meta Matrix Factorization Against Strict Privacy Constraints

March 30, 2021

at 43rd European Conference on IR Research (ECIR) 2021, Online

Grants

• Travel Grant: RecSys Summer School, 2023 (Copenhagen, Denmark)
• Student Grant: 45th European Conference on Information Retrieval, 2023 (Dublin, Ireland)

Program Committee and Reviewing

• UMAP 2023: 31th Conference on User Modeling, Adaptation and Personalization
• Frontiers in Big Data 2023: Recommender Systems Series
• HT 2023: 34rd ACM Conference on Hypertext and Social Media
• WWW 2023: The Web Conference
• IUI 2023: 28th International Conference on Intelligent User Interfaces
• Perspectives 2022: Perspectives on the Evaluation of Recommender Systems, Workshop held in conjunction with ACM Recommender Systems
• CIKM 2022: 31st ACM International Conference on Information and Knowledge Management
• RecSys 2022: 16th ACM Conference on Recommender Systems
• HAAPIE 2022: Human Aspects in Adaptive and Personalized Interactive Environments, Workshop held in conjunction with UMAP
• ICWE 2022: 22nd International Conference on Web Engineering
• HT 2022: 33rd ACM Conference on Hypertext and Social Media
• TiiS 2022: ACM Transactions on Interactive Intelligent Systems
• IUI 2022: 27th International Conference on Intelligent User Interfaces
• TiiS 2021: ACM Transactions on Interactive Intelligent Systems
• Perspectives 2021: Perspectives on the Evaluation of Recommender Systems, Workshop held in conjunction with ACM Recommender Systems
• ASOC 2021: Journal of Applied Soft Computing
• CIKM 2021: 30th ACM International Conference on Information and Knowledge Management
• HT 2021: 32nd ACM Conference on Hypertext and Social Media
• UMAP 2021: 29th Conference on User Modeling, Adaptation and Personalization
• IUI 2021: 26th International Conference on Intelligent User Interfaces
• HT 2020: 31st ACM Conference on Hypertext and Social Media
• EC-TEL 2020: 15th European Conference on Technology Enhanced Learning
• ECML/PKDD 2020: 20th European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases