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    • About ACM Awards

      Giving Credit where Credit Is Due

      ACM recognizes excellence through its eminent awards for technical and professional achievements and contributions in computer science and information technology. It also names as Fellows and Distinguished Members those members who, in addition to professional accomplishments, have made significant contributions to ACM's mission. ACM awards recognize achievements by young computing professionals, educators, theoretical computer scientists, software systems innovators, and pioneers who have made humanitarian and cross-discipline contributions.

    • 2024 ACM A.M. Turing Award recipients Andrew G. Barto and Richard S. Sutton
      Andrew Barto and Richard Sutton Receive 2024 ACM A.M. Turing Award
      2024 ACM Prize recipient Torsten Hoefler
      Torsten Hoefler Receives 2024 ACM Prize in Computing
      2025-2026 ACM Athena Lecturer Cordelia Schmid
      ACM Names Cordelia Schmid 2025-2026 Athena Lecturer
  • Advanced Member Grades
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    • ACM Advanced Grades of Membership

      The ACM Advanced Grades of Membership program recognizes the achievements of ACM members through all stages of their career.

    • acm-fellows-member-badge.jpg
      ACM Names 2023 Fellows
      acm-distinguished-member-badge.jpg
      ACM Names 2023 Distinguished Members
  • SIG Awards
    • About SIG Awards
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    • About SIG Awards

      ACM's Special Interest Groups (SIGs) regularly cite outstanding individuals for their contributions in more than 30 distinct technological fields.

  • Regional Awards
    • About Regional Awards
      • ACM India Doctoral Dissertation
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      • CCF-ACM Award for Artificial Intelligence

    • About ACM Regional Awards

      ACM recognizes the contributions of individuals working primarily within specific regions of the world through awards given by its regional councils, and through partnerships with international societies.

    • Dr. Arkaprava Basu and Dr. Sayan Ranu
      ACM India ECR 2024 Award
      Prof. Hemangee Kapoor
      ACM India OCCW 2024 Award
      OCCE 2024 award recipient Meenakshi D'Souza
      ACM India OCCE 2024 Award
  • Nominations
    • Award Nominations
      • ACM A.M. Turing Award
      • ACM Prize in Computing
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      • ACM Frances E. Allen Award
      • ACM Luiz André Barroso Award
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      • ACM-IEEE CS Eckert-Mauchly Award
      • ACM Gordon Bell Prize
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      • ACM Karl V. Karlstrom Outstanding Educator Award
      • ACM-IEEE CS Ken Kennedy Award
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    • Awards Nominating Process

      How to Nominate

      Award nominations deadlines occur throughout the year, with a heavy concentration in January. Please refer to the Nomination Process page for each award, which includes not only information about the deadline but also guidance for preparing each type of nomination.  ACM's conflict-of-interest guidelines apply to all award nominations.

    • acm-w-rising-star-award.jpg
      Call for ACM-W Rising Star Award Nominations
      og-awards.jpg
      ACM Honors & Ethics
  • Honors and Ethics
    • Policy for Honors Conferred by ACM
      • Policies and Procedures for Honors Conferred by ACM

    • ACM Honors and Ethics

      ACM formally recognizes individuals for significant contributions to the field, ACM, or its interests. ACM expects individuals it honors to abide by the ACM Code of Ethics and Professional Conduct. Learn about ACM's policies and procedures for integrating expectations of ethical behaviour and ACM Awards.

    • acm-w-rising-star-award.jpg
      Call for ACM-W Rising Star Award Nominations
      og-awards.jpg
      ACM Honors & Ethics
  • Awards Committees
    • ACM Awards Committee
      • ACM A.M. Turing Award Committee
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      • ACM Grace Murray Hopper Award Committee
      • ACM Paris Kanellakis Theory and Practice Award Committee
      • ACM Karl V. Karlstrom Outstanding Educator Award Committee
      • ACM-IEEE CS Ken Kennedy Award Committee
      • ACM Eugene L. Lawler Award Committee
      • ACM-IEEE CS George Michael Memorial HPC Fellowships Committee
      • ACM AAAI Allen Newell Award Committee
      • Outstanding Contribution to ACM Award Committee
      • ACM Policy Award Committee
      • SIAM/ACM Prize in Computational Science and Engineering Committee
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      • ACM India Doctoral Dissertation Award Committee
      • ACM Fellows Committee
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      • ACM Senior Member Committee
      • Conflict of Interest Guidelines

    • About ACM Awards Committees

      At the core of the ACM Awards program is a dedicated group of volunteers who serve on the committees of the ACM Awards to recognize individuals for their excellence in the computing fields

    • awards-ctte-co-chairs.jpg
  • Establishing an Award
    • Policies and Guide for Establishing an ACM Award
      • ACM Publications Board Guidelines for Establishing a Best Paper Award for ACM Periodicals

    • Policies and Guide

      ACM welcomes proposals for the establishment of new awards, to recognize contributions based on merit, service, or for an outstanding paper.

    • acm-w-rising-star-award.jpg
      Call for ACM-W Rising Star Award Nominations
      og-awards.jpg
      ACM Honors & Ethics
  • Home
  • Award Recipients
  • Hector Geffner

Hector Geffner

Digital Library
  • ACM Doctoral Dissertation Award (1990)

ACM Doctoral Dissertation Award

USA - 1990

citation

For his dissertation "Default Reasoning: Casual and Conditional Theories."

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