Disputation: Vinit Ravishankar

Doctoral candidate Vinit Ravishankar at the Department of Informatics, Faculty of Mathematics and Natural Sciences, is defending the thesis Understanding Multilingual Language Models: Training, Representation and Architecture for the degree of Philosophiae Doctor.

Picture of the candidate

Photo: Private

The PhD defence and trial lecture will be fully digital and streamed directly using Zoom. The host of the session will moderate the technicalities while the chair of the defence will moderate the disputation.

Ex auditorio questions: the chair of the defence will invite the audience to ask ex auditorio questions either written or oral. This can be requested by clicking 'Participants -> Raise hand'. 

Trial lecture

  • June 16, 2023 11:15 AM, in Zoom
  • Join the trial lecture
  • Title: "Faithfulness evaluation of interpretability techniques in NLP"

 

Main research findings

The field of natural language processing has seen numerous advancements since its inception during the Cold War, when attempts were made to automate translating Russian text to English. The 2010s have been a particularly fertile decade, going by sheer research volume – the use of a class of machine learning models known as neural networks has led to substantial improvements in performance on a broad range of language-related tasks, ranging from classification, to summarisation, to machine translation. In addition, some of these models have demonstrated an excellent multilingual capacity, where they can be trained to process text in English, and with only a bit of extra data, show solid results across languages. Yet these improvements, rapid as they have been, are not without their drawbacks. One such drawback is that we lack the tools to rationalise how and why these models function, particularly given the many (often arbitrary) decisions that went into their design. This dissertation adopts multiple analytical frameworks in an effort to answer questions surrounding the behaviour of multilingual neural models. How does the data they were trained on affect their performance? What linguistic capabilities can they exhibit? And finally, how do different model components help enable multilinguality?

Adjudication committee:

  • Professor Barbara Plank, Center for Information and Language Processing, Ludwig-Maximilians-Universität München, Germany

  • Associate Professor Willem Zuidema, Institute for Logic, Language and Computation, University of Amsterdam, the Netherlands

  • Associate Professor Kai Olav Ellefsen, Department of Informatics, University of Oslo, Norway

Supervisors

  • Professor Lilja Øvrelid, Department of Informatics, University of Oslo, Norway
  • Professor Erik Velldal, Department of Informatics, University of Oslo, Norway 

Chair of defence:

Professor, Head of Department Stephan Oepen

 

Contact information at Department: Pernille Adine Nordby 

Published June 5, 2023 10:08 AM - Last modified June 13, 2023 1:00 PM