PeopleofSuperintelligence

Researcher

Nicolaas J. I. Mars

Nicolaas Mars is an AI researcher whose work includes medical expert systems, knowledge acquisition and ontologies. He coauthors HYDRA in 1987, a computer-based tool for developing expert systems that critique medical workups, and publishes a University of Twente review of natural-language knowledge acquisition in 1991. In 1994, he chairs the organizing committee for an ECAI ontology workshop while affiliated with the University of Twente. He publishes a 306-page book on very large knowledge bases in 1995 and serves as EurAI president from 1995 to 1996. He coauthors a bottom-up ontology method in 1998 and a topographic-data integration framework in 2005; as of October 2026, he is a EurAI Fellow affiliated with Rijksuniversiteit Groningen.

Works
187
Citations
1,130
h-index
15
Badges

Publication numbers from OpenAlex, as of 22 October 2026.

Timeline

  1. 1987

    HYDRA and medical expert systems

    He coauthors HYDRA in 1987, a computer-based knowledge-acquisition tool that supports the creation of expert systems that critique medical workups.

  2. 1991

    Natural-language knowledge review

    At the University of Twente, he publishes a report in 1991 that reviews knowledge acquisition from natural-language texts.

  3. 1994

    ECAI workshop committee chair

    In 1994, he chairs the organizing committee for the ECAI'94 Workshop on Comparison of Implemented Ontologies while affiliated with the University of Twente's Department of Computer Science.

  4. 1995

    An IOS knowledge-base book

    In 1995, he publishes a 306-page book through IOS titled Towards very large knowledge bases, knowledge building and knowledge sharing.

  5. 1995–1996

    President of EurAI

    He serves as EurAI president from 1995 to 1996.

  6. 1998

    Bottom-up ontology construction

    With Paul E. van der Vet, he presents a bottom-up method for building ontologies in a 1998 paper. The method defines concepts through the composition of smaller objects.

  7. 2005

    Integrating topographic data sets

    He coauthors a framework for integrating topographic data sets in 2005. It combines ontologies and surveying rules with a reference model unique to each data-set combination.

  8. As of October 2026

    EurAI Fellow in Groningen

    As of October 2026, he is a EurAI Fellow affiliated with Rijksuniversiteit Groningen.

Career

  1. Since 2005University of Groningen
  2. 1982–1985Leiden University
  3. 1980–1994University of Twente
  4. European Association for Artificial IntelligencePresident

From the biography and OpenAlex affiliations (the years of papers that list the organization), so some years are approximate.

Most-cited works

  1. Towards very large knowledge bases, knowledge building and knowledge sharing 19951995 · 232 citations
  2. Towards Very Large Knowledge Bases1995 · IOS Press eBooks · 132 citations
  3. Bottom-up construction of ontologies1998 · IEEE Transactions on Knowledge and Data Engineering · 129 citations
  4. Ontology-Based Geographic Data Set Integration1999 · Lecture notes in computer science · 96 citations
  5. Experiment selection for the discrimination of semi-quantitative models of dynamical systems2005 · Artificial Intelligence · 82 citations

From OpenAlex, as of 21 October 2026.

  1. More people shaping AI studied at Massachusetts Institute of Technology than at any other institutionIncludes University of Groningen. We estimate where the people shaping AI studied and where their careers led. Massachusetts Institute of Technology leads with 467 former students, including 291 recorded doctorates.
  2. The company share of AI researchers’ top papers was 31% in 2020–2024 and 8% in 1970–1974Includes University of Groningen. We estimate where the people shaping AI worked when their most-cited papers appeared: the company share was 31% in 2020–2024 and 8% in 1970–1974, and Google led all organizations in 2020–2024.
  3. The Massachusetts Institute of Technology trained or employed 44 of the 187 AI major-prize winners, more than any other universityIncludes University of Groningen. The Massachusetts Institute of Technology trained or employed 44 of the 187 AI major-prize winners, more than any other university. We compare doctorate and 5+ year employment links, career timing and current workplaces for 187 major-prize and 1,111 best-paper winners.
  4. Google has the highest combined h-index among AI organizationsIncludes Leiden University. We estimate that Google holds the highest combined h-index at 8,016, while universities account for 73% of the deduplicated total across AI organizations.

Colleagues

People with dated positions at the same organization in the same years.

Sources and credits

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  1. Hydra ideas.repec.org. Checked 21 October 2026.
  2. Knowledge acquisition from natural-language texts. A review of the literature - University of Twente Research Information research.utwente.nl. Checked 21 October 2026.
  3. CFP: ECAI94 Workshop on Comparison of Implemented Ontologies site.uottawa.ca. Checked 21 October 2026.
  4. Towards very large knowledge bases, knowledge building and knowledge sharing 1995 - University of Twente Research Information research.utwente.nl. Checked 21 October 2026.
  5. EurAI Board | European Association for Artificial Intelligence eurai.org. Checked 21 October 2026.
  6. Bottom-up construction of ontologies - University of Twente Research Information research.utwente.nl. Checked 21 October 2026.
  7. Ontology-based integration of topographic data sets - the University of Groningen research portal research.rug.nl. Checked 21 October 2026.
  8. EurAI honors – http://ii.tudelft.nl/bnvki/ ii.tudelft.nl. Checked 21 October 2026.
  9. Awards | European Association for Artificial Intelligence eurai.org. Checked 21 October 2026.