I am a researcher in Natural Language Processing and Information Retrieval, currently working as a Research Assistant at the University of Toronto. I completed my M.A.Sc. in Computer Engineering at the University of Guelph. During my master’s, I worked at the LS3 under the supervision of Dr. Ebrahim Bagheri and Dr. Fattane Zarrinkalam.
My research focuses on two main directions. The first is diffusion-based generative ranking, where I explore how denoising diffusion models can be adapted to improve ranking effectiveness in search and retrieval tasks. The second is enhancing the peer-review process, designing models and tools to evaluate and improve review quality, with the goal of making scholarly evaluation more consistent, transparent, and fair.
I have published multiple papers in venues such as SIGIR, WSDM, and CIKM, and combine my research with industry experience as a Data Scientist, where I design and deploy large-scale ranking systems, vector search infrastructures, and NLP pipelines. Currently, I am working at Reviewerly, developing and maintaining large-scale scholarly search and matching systems used in peer-review and grant assignment.
You can find my CV here.
🔥 News
- [2026/01] Our demo paper "PeeriScope: A Multi-Faceted Framework for Evaluating Peer Review Quality" got accepted at WebConf 2026. Try Peeriscope now and see how your reviews measure up!
- [2025/12] I successfully defended my M.A.Sc. thesis 🎓.
- [2025/12] Our proposal for a presentation in the Industry Day talks, "Can LLMs Uphold Research Integrity? Evaluating the Role of LLMs in Peer Review Quality", got accepted at WSDM 2026.
- [2025/11] I attended the CIKM 2025 conference in Seoul, South Korea. I also had my first experience organizing a workshop, which was a valuable learning opportunity. It was especially rewarding to see strong community interest and engagement with our workshop.
- [2025/10] I attended the COLM 2025 conference in Montreal, Canada.
- [2025/08] Our paper "Query Performance Prediction Using Neural Query Space Proximity" got accepted at TIST.
- [2025/08] Our paper "RottenReviews: Benchmarking Review Quality with Human and LLM-Based Judgments" got accepted at the CIKM 2025.
- [2025/08] Our proposal for a presentation in the Industry Day talks, "Building Trustworthy Peer Review Quality Assessment Systems", got accepted at CIKM 2025.
- [2025/08] I attended the KDD 2025 conference in Toronto, Canada. I served as a student volunteer for the first time and loved the experience!
- [2025/07] I am co-organizing the ProActLLM workshop at CIKM 2025 which explores proactive and adaptive behaviors of LLMs. Submit your work and be part of the conversation!
- [2025/04] I attended the ECIR 2025 conference in Lucca, Italy.
- [2025/04] Our paper "Reinforcement Learning for Effective Few-Shot Ranking" got accepted at SIGIR 2025.
- [2025/03] Our paper "Estimating Query Performance Through Rich Contextualized Query Representations" got accepted for oral presentation at the QPP++ workshop.
- [2025/03] I won the Braithwaite Conference Travel Grant to attend the ECIR 2025 conference.
- [2024/12] Our paper "exHarmony: Authorship and Citations for Benchmarking the Reviewer Assignment Problem" got accepted at ECIR 2025.
- [2024/12] I presented "It Takes a Team to Triumph: Collaborative Expert Finding in Community QA Networks" paper at the SIGIR-AP 2024 conference.
- [2024/12] I attended the SIGIR-AP 2024 conference in Tokyo, Japan.
- [2024/12] I attended the ACML 2024 conference in Hanoi, Vietnam.
- [2024/11] I won the Braithwaite Conference Travel Grant to attend the SIGIR-AP 2024 conference.
- [2024/11] I won the Braithwaite Conference Travel Grant to attend the ACML 2024 conference.
- [2024/09] Our paper "Gender Disentangled Representation Learning in Neural Rankers" got accepted at Machine Learning Journal (MLJ).
- [2025/08] Our proposal for a presentation in the Industry Day talks, "Reviewerly: Modeling the Reviewer Assignment Task as an Information Retrieval Problem", got accepted at CIKM 2024.
- [2024/05] I attended the Canadian AI 2024 conference in Guelph, Canada.
- [2024/05] I presented Reviewerly at the First OpenAlex User Conference.
- [2024/03] I attended the ECIR 2024 conference in Glasgow, Scotland. It marked my introduction to the research community and my first time engaging with key figures in the field!
- [2024/03] I won the Braithwaite Conference Travel Grant to attend the ECIR 2024 conference.
- [2023/12] Milestone unlocked: my first paper acceptance! Our paper "Estimating Query Performance Through Rich Contextualized Query Representations" got accepted at ECIR 2024.
- [2023/11] I started working as a Data Scientist at Reviewerly, focusing on information retrieval, ranking, and large-scale data mining.
- [2023/10] I won the CEPS Dean’s Graduate Entrance Scholarships for the Fall 2023 semester.
- [2023/09] I started my M.A.Sc. in Computer Engineering at the University of Guelph.
- [2023/04] I won the Entrance Award in Recognition of Student Excellence in the College of Engineering and Physical Sciences at the University of Guelph.
- [2023/07] I graduated with a B.Sc. in Computer Engineering from Ferdowsi University of Mashhad.
📝 Publications
- From Noise to Order: Learning to Rank via Denoising Diffusion [pdf] [code]
Sajad Ebrahimi, Bhaskar Mitra, Negar Arabzadeh, Ye Yuan, Haolun Wu, Fattane Zarrinkalam, Ebrahim Bagheri
Preprint - Can LLMs Uphold Research Integrity? Evaluating the Role of LLMs in Peer Review Quality [pdf]
Negar Arabzadeh, Sajad Ebrahimi, Soroush Sadeghian, Mohammad Hosseini, Alireza Daqiq, Hai Son Le, Mahdi Bashari, Ebrahim Bagheri
Industry Day at WSDM 2026: 19th ACM International Conference on Web Search and Data Mining - Query Performance Prediction Using Neural Query Space Proximity [pdf] [code]
Amin Bigdeli, Sajad Ebrahimi, Negar Arabzadeh, Sara Salamat, Shirin SeyedSalehi, Maryam Khodabakhsh, Fattane Zarrinkalam, Ebrahim Bagheri
ACM Transactions on Intelligent Systems and Technology (TIST) - RottenReviews: Benchmarking Review Quality with Human and LLM-Based Judgments [pdf] [code] [data]
Sajad Ebrahimi, Soroush Sadeghian, Ali Ghorbanpour, Negar Arabzadeh, Sara Salamat, Muhan Li, Hai Son Le, Mahdi Bashari and Ebrahim Bagheri
CIKM 2025: 34th ACM International Conference on Information and Knowledge Management - Building Trustworthy Peer Review Quality Assessment Systems
Negar Arabzadeh, Sajad Ebrahimi, Ali Ghorbanpour, Soroush Sadeghian, Sara Salamat, Muhan Li, Hai Son Le, Mahdi Bashari, Ebrahim Bagheri
Industry Day at CIKM 2025: 34th ACM International Conference on Information and Knowledge Management - ProActLLM: Proactive Conversational Information Seeking with Large Language Models
Shubham Chatterjee, Xi Wang, Shuo Zhang, Sajad Ebrahimi, Zhaochun Ren, Debasis Ganguly, Gareth Jones, Emine Yilmaz, Hamed Zamani
CIKM 2025: 34th ACM International Conference on Information and Knowledge Management - exHarmony: Authorship and Citations for Benchmarking the Reviewer Assignment Problem [pdf] [code] [data]
Sajad Ebrahimi*, Sara Salamat*, Negar Arabzadeh, Mahdi Bashari, Ebrahim Bagheri
ECIR 2025: 47th European Conference on Information Retrieval - Reinforcement Learning for Effective Few-Shot Ranking [pdf]
Shiva Soleimany, Sajad Ebrahimi, Shirin SeyedSalehi, Fattane Zarrinkalam, Ebrahim Bagheri
SIGIR 2025: 48th International ACM SIGIR Conference on Research and Development in Information Retrieval - Gender Disentangled Representation Learning in Neural Rankers [pdf] [code]
Shirin SeyedSalehi, Sara Salamat, Negar Arabzadeh, Sajad Ebrahimi, Morteza Zihayat, Ebrahim Bagheri
Machine Learning Journal (MLJ) - Reviewerly: Modeling the Reviewer Assignment Task as an Information Retrieval Problem [pdf]
Negar Arabzadeh, Sajad Ebrahimi, Sara Salamat, Mahdi Bashari, Ebrahim Bagheri
Industry Day at CIKM 2024: 33rd ACM International Conference on Information and Knowledge Management - Estimating Query Performance Through Rich Contextualized Query Representations [pdf] [poster] [slides] [code]
Sajad Ebrahimi, Maryam Khodabakhsh, Negar Arabzadeh, Ebrahim Bagheri
ECIR 2024: 46th European Conference on Information Retrieval
💬 Presentations and Talks
- RottenReviews: Benchmarking Review Quality with Human and LLM-Based Judgments [slides]
CIKM 2025, November 2025 - Estimating Query Performance Through Rich Contextualized Query Representations [slides]
QPP++ 2025, April 2025 - It Takes a Team to Triumph: Collaborative Expert Finding in Community QA Networks [slides]
SIGIR-AP’24, December 2024 - Reviewerly: A High Quality Peer Reviewer Suggestion Application [recording] [slides]
2024 OpenAlex Virtual User Conference, May 2024 - Introduction to Neural Information Retrieval [code] [slides]
Special Topics in Information Retrieval-University of Guelph, November 2023