Cracking Crosswords: The Computer Challenge

  • Marco Gori
  • Marco Ernandes
  • Giovanni Angelini
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4155)


Crosswords is over 90 years old, yet it is still one of the most popular puzzles around the world. It is in fact a linguistic game which requires a wide knowledge in different domains and the ability to crack enigmatic clues, that are often regarded as inherent human capabilities. Unlike chess, crossword solving does not require strong skills for the actuation of strategic plans, but the linguistic specifications is in itself a source of enormous difficulty for machines.

This paper discusses the problem of automatic crossword solving with special emphasis to the WebCrow project carried out at the University of Siena. After a brief historical description of the evolution of crosswords, the paper gives a formalization of the main problems to be faced and provides a number of relevant architectural issues behind cracking crosswords. In particular, it is claimed that the Web is likely to be the most important source for the development of challenging programs based on clue answering, a sort of question answering mechanism in which the machine is expected to return candidate word solutions.


Correct Answer Candidate List Compound Word Statistical Filter Correct Word 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Marco Gori
    • 1
  • Marco Ernandes
    • 1
  • Giovanni Angelini
    • 1
  1. 1.Dipartimento di Ingegneria dell’InformazioneSienaItaly

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