Human-Centred Feasibility Restoration

Authors Ilankaikone Senthooran , Matthias Klapperstueck , Gleb Belov , Tobias Czauderna , Kevin Leo , Mark Wallace , Michael Wybrow , Maria Garcia de la Banda

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  • 18 pages

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Author Details

Ilankaikone Senthooran
  • Data Science & AI, Monash University, Clayton, Australia
Matthias Klapperstueck
  • Human-Centred Computing, Monash University, Clayton, Australia
Gleb Belov
  • Data Science & AI, Monash University, Clayton, Australia
Tobias Czauderna
  • Human-Centred Computing, Monash University, Clayton, Australia
Kevin Leo
  • Data Science & AI, Monash University, Clayton, Australia
Mark Wallace
  • Data Science & AI, Monash University, Clayton, Australia
Michael Wybrow
  • Human-Centred Computing, Monash University, Clayton, Australia
Maria Garcia de la Banda
  • Data Science & AI, Monash University, Clayton, Australia

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Ilankaikone Senthooran, Matthias Klapperstueck, Gleb Belov, Tobias Czauderna, Kevin Leo, Mark Wallace, Michael Wybrow, and Maria Garcia de la Banda. Human-Centred Feasibility Restoration. In 27th International Conference on Principles and Practice of Constraint Programming (CP 2021). Leibniz International Proceedings in Informatics (LIPIcs), Volume 210, pp. 49:1-49:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2021)


Decision systems for solving real-world combinatorial problems must be able to report infeasibility in such a way that users can understand the reasons behind it, and understand how to modify the problem to restore feasibility. Current methods mainly focus on reporting one or more subsets of the problem constraints that cause infeasibility. Methods that also show users how to restore feasibility tend to be less flexible and/or problem-dependent. We describe a problem-independent approach to feasibility restoration that combines existing techniques from the literature in novel ways to yield meaningful, useful, practical and flexible user support. We evaluate the resulting framework on two real-world applications.

Subject Classification

ACM Subject Classification
  • Theory of computation → Constraint and logic programming
  • Theory of computation → Integer programming
  • Combinatorial optimisation
  • modelling
  • human-centred
  • conflict resolution
  • feasibility restoration
  • explainable AI
  • soft constraints


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