Evaluation and Optimization of Word Disambiguation for Text-Entry Methods

  • Hamed  H. SadEmail author
  • Franck Poirier
Conference paper


We study the key-characters assignment on ambiguous keyboards. We consider two cases: unconstrained and alphabetically constrained character arrangements on ambiguous keys. A genetic algorithm is used for searching the assignment that optimizes the text-entry performance. The results show that as the number of keys decreases, the gain in performance due to optimization increases. We also study the effect of the disambiguation word list layout on the text-entry usability. We demonstrate that adding words by completion to the word list always leads to better performance. The usability effect of changing the number of ambiguous keys, compared to changing the number of words displayed to the user, is investigated.


Mobile Device Word List Text Entry Candidate Word Standard Telephone 
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 London Limited 2009

Authors and Affiliations

  1. 1.Université de Bretagne-SudVALORIA – Centre de RechercheFrance

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