Kidist Amde Mekonnen

I am an ELLIS PhD Candidate at the Information Retrieval Lab of the University of Amsterdam, supervised by Prof. dr. Maarten de Rijke, with Dr. Andrew Yates as my co-promoter. My research focuses on generative modelling, representation learning, and ranking for personalized retrieval and recommendation.

More broadly, I am interested in semantic and multimodal representations, scalable identifier learning, continual learning, and LLM-based retrieval and recommendation. I am particularly interested in how learned representations and generative models can support large-scale personalized systems that adapt to changing users, items, and collections.

I also have a strong interest in multilingual and low-resource information retrieval, particularly for underrepresented languages.

💡 Research Highlights

• Document-level relevance optimization: designing lightweight learning objectives that directly align generative retrieval models with document-level relevance.

• Continual generative retrieval: developing parametric-memory mechanisms that incorporate new documents while preserving previously learned knowledge.

• Decoding and robustness: studying how constrained generation and look-ahead guidance affect recall under query variation and distribution shift.

• Multilingual and low-resource retrieval: developing retrieval models and benchmarks for Amharic and other underrepresented languages.

• Generative recommendation: exploring semantic and multimodal item identifiers, constrained generation, and scalable identifier learning.

• Retrieval-augmented systems: contributing to multi-turn pipelines that combine sparse retrieval, query reformulation, reranking, and generation.

📢 News & Updates

• 🇬🇧 November 2026 — I will undertake an ELLIS research exchange at University College London (UCL), hosted by Prof. Emine Yilmaz.

• August 2026 — I joined Booking.com as a PhD Machine Learning Research Intern, working on scalable and generalisable ID embedding learning.

• 🇦🇺 July 2026 — I presented two papers at SIGIR 2026 in Melbourne, Australia: “A Parametric Memory Head for Continual Generative Retrieval” [Paper] and “Lost in Decoding? Reproducing and Stress-Testing the Look-Ahead Prior in Generative Retrieval” [Paper].

• July 2026 — Our paper, “The Multilingual Curse at the Retrieval Layer: Evidence from Amharic,” appeared at MeLLM @ ACL 2026. [Paper]

• 🏆 June 2026 — Our uva-irlab-conv system, combining learned sparse retrieval with conversational query rewriting and listwise reranking, ranked 2nd out of 38 teams in the conversational search subtask of the SemEval-2026 Multi-Turn RAG Shared Task (Task 8). [Paper]

• 🔥 May 2026 — Our paper on multilingual retrieval for Amharic was accepted at MeLLM @ ACL 2026. [Paper]

• 🔥 April 2026 — Two papers were accepted at SIGIR 2026: a full paper on continual generative retrieval [Paper] and a reproducibility paper on decoding robustness [Paper].

• 🇦🇹 July 2025 — Presented our paper, “Optimized Text Embedding Models and Benchmarks for Amharic Passage Retrieval,” at ACL 2025 in Vienna, Austria. [Paper]

• 🇮🇹 July 2025 — Presented our paper, “Lightweight and Direct Document Relevance Optimization for Generative Information Retrieval,” at SIGIR 2025 in Padova, Italy. [Paper]

• 🔥 May 2025 — Our paper, “Optimized Text Embedding Models and Benchmarks for Amharic Passage Retrieval,” was accepted for publication in Findings of ACL 2025. [Paper]

• 🔥 April 2025 — Our full paper, “Lightweight and Direct Document Relevance Optimization for Generative Information Retrieval,” was accepted at SIGIR 2025. [Paper]

🎓 Education and Experience

• 2026–Present, PhD Machine Learning Research Intern, Booking.com

• 2023–Present, ELLIS PhD Candidate, University of Amsterdam, The Netherlands

• Apr. 2022–Oct. 2022, Data Science Research Intern, Nanovery, Newcastle upon Tyne, United Kingdom

• 2020–2023, MSc in Data Science, University of Trento, Italy

• 2019–2020, MSc in Machine Intelligence, African Institute for Mathematical Sciences / AMMI, Rwanda

• 2017–2019, Assistant Lecturer, Department of Computer Science, University of Gondar, Ethiopia

• 2013–2017, BSc in Computer Science, University of Gondar, Ethiopia