Rishiraj Saha Roy


Rishiraj Saha Roy

Rishiraj Saha Roy

Max-Planck-Institut für Informatik
Department 5: Databases and Information Systems
 office: Campus E1 4, Room 408
Saarland Informatics Campus
66123 Saarbrücken
 email: Get my email address via email
 phone: +49 681 9325-5008


Rishiraj Saha Roy is a Senior Researcher at the Max Planck Institute for Informatics (MPII), Saarbruecken, Germany, leading the research group on Question Answering, that focuses on robust and interpretable solutions for answering natural language questions over structured and unstructured sources. He also has a parallel thread of work on explainability in online services, conducted in scope of the research on the imPACT project. Rishiraj belongs to the Databases and Information Systems Department, that is headed by MPII director Prof. Gerhard Weikum. In general, he is really passionate about applying language technology in and around text-based search. Prior to joining MPII, he worked for one and a half years as a Computer Scientist at Adobe Research, Bangalore, India. At Adobe, he worked on various text mining use cases involving the Adobe Marketing Cloud and the Adobe Document Cloud product lines. He completed his PhD as a Microsoft Research India PhD Fellow from the Indian Institute of Technology (IIT) Kharagpur, working under the supervision of Prof. Niloy Ganguly (IIT Kharagpur) and Dr. Monojit Choudhury (Microsoft Research India). During his PhD, he explored Web search query understanding, working on aspects like query segmentation, query intent discovery, and query complexity analysis. He did his masters' at IIT Roorkee (a beautiul town near Hardwar, India) and his bachelors' at Jadavpur University, Kolkata, India. He was born and brought up in the City of Joy. When not working, he can often be found poring over all kinds of word and logic puzzles.

What's New?

  • [29 April 2021] Invited talk on "Learning from User Feedback on Explanations to Improve Recommender Models" at Flipkart, Bangalore, India.
  • [14 April 2021] Our full paper "Reinforcement Learning from Reformulations in Conversational Question Answering over Knowledge Graphs" is accepted at SIGIR '21 (with Magdalena Kaiser and Gerhard Weikum). [Preprint] [Data+Demo]
  • [14 April 2021] Our short paper "Counterfactual Explanations for Neural Recommenders" is accepted at SIGIR '21 (with Khanh Hiep Tran and Azin Ghazimatin). [Preprint] [Code]
  • [01 April 2021] PC Member of CIKM '21.
  • [30 March 2021] PC Member of EMNLP '21.
  • [05 March 2021] New PhD student Philipp Christmann will join our group on 15 April 2021.
  • [10 February 2021] Outstanding Senior Program Committee Member at AAAI '21.
  • [15 January 2021] Our full paper ELIXIR: Learning from User Feedback on Explanations to Improve Recommender Models is accepted at WWW '21 (with Azin Ghazimatin, Soumajit Pramanik, and Gerhard Weikum). [Preprint] [Data and code] [Slides] [Video]
  • [28 December 2021] Delivered a guest lecture in the Information Retrieval Course at the Department of Computer Science and Engineering, IIT Delhi, on "Question Answering over Knowledge Graphs".
  • [18 December 2021] Outstanding Reviewer at EMNLP '20.

Research Interests

Selected Publications

[Google Scholar] [DBLP]


Employment Positions



Professional Activities

  • Selected conference PCs: WSDM (2021), SIGIR (2019 - 2021), CIKM (2020 - 2021), AAAI (2020), IJCAI (2021), ACL (2020 - 2021), EMNLP (2017 - 2021), NAACL-HLT (2019 - 2021); Senior PC: AAAI (2021)
  • Selection committee member for Masters' Students for the Computer Science Department at the Saarland University. (2019 - Present)
  • Publications Chair of the CoDS-COMAD 2020, 5 - 7 January 2020, Hyderabad, India.
  • Co-organizer of the IR Track at KSE 2019, 24 - 26 October 2019, Da Nang, Vietnam. (with Md. Zia Ullah)
  • Co-editor of Dynamics On and Of Complex Networks III, Springer, 16 June 2019 (with Fakhteh Ghanbarnejad, Fariba Karimi, Jean-Charles Delvenne, and Bivas Mitra).
  • Co-organizer of the DOOCN 2019, 28 May 2019, Vermont, USA. (with Fakhteh Ghanbarnejad, Parantapa Bhattacharya, and Sandipan Sikdar)
  • Co-organizer of the COMSNETS SN 2019, 11 January 2019, Bangalore, India. (with Saptarshi Ghosh)
  • Publications Chair of the CoDS-COMAD 2019, 3 - 5 January 2019.
  • Co-organizer of the DOOCN 2018, 27 September 2018, Thessaloniki, Greece. (with Jean-Charles Delvenne, Fakhteh Ghanbarnejad, Fariba Karimi, Bivas Mitra, and Parantapa Bhattacharya)
  • Co-organizer of the COMSNETS SN 2018, 7 January 2018, Bangalore, India. (with Moumita Sinha)
  • Co-organizer of the DOOCN 2017, 19 June 2017, Indianapolis, USA. (with Jean-Charles Delvenne, Fakhteh Ghanbarnejad, Fariba Karimi, and Bivas Mitra)
  • Co-organizer of the shared task on "Transliterated Search" at the FIRE 2013, 4 – 6 December 2013, New Delhi, India. (with Monojit Choudhury, Prasenjit Majumder, and Komal Agarwal)

Invited Talks



PhD Students Masters' Students
  • Philipp Christmann (2020 - 2021)
  • Khanh Hiep Tran (2020 - 2021)
  • David Ziegler (2016 - 2017)
  • Sedigheh Eslami (2016 - 2017)
Bachelors' Students
  • Philipp Christmann (2018 - 2019)
  • Jana Schmidt (2017 - 2018)


  • Cricket
  • Photography
  • Table Tennis
  • Word puzzles
  • Quizzing
  • Philately
  • Swimming
  • Taekwondo