Conditional lexicographic orders in constraint satisfaction problems

@article{Wallace2009ConditionalLO,
  title={Conditional lexicographic orders in constraint satisfaction problems},
  author={Richard J. Wallace and Nic Wilson},
  journal={Annals of Operations Research},
  year={2009},
  volume={171},
  pages={3-25}
}
The lexicographically-ordered CSP (“lexicographic CSP” or “LO-CSP” for short) combines a simple representation of preferences with the feasibility constraints of ordinary CSPs. Preferences are defined by a total ordering across all assignments, such that a change in assignment to a given variable is more important than any change in assignment to any less important variable. In this paper, we show how this representation can be extended to handle conditional preferences in two ways. In the… 
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The lexicographically-ordered CSP (“lexicographic CSP” for short) combines a simple representation of preferences with the feasibility constraints of ordinary CSPs, to support powerful methods for
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