On the Inherent Level of Local Consistency in Constraint Networks

We present a new property called constraint looseness and show how it can be used to estimate the level of local consistency of a binary constraint network. Speci cally, we present a relationship between the looseness of the constraints, the size of the domains, and the inherent level of local consistency of a constraint network. The results we present are useful in two ways. First, a common method for nding solutions to a constraint network is to rst preprocess the network by enforcing local consistency conditions, and then perform a backtracking search. Here, our results can be used in deciding which low-order local consistency techniques will not change a given constraint network and thus are not useful for preprocessing the network. Second, much previous work has identi ed conditions for when a certain level of local consistency is su cient to guarantee a network is backtrack-free. Here, our results can be used in deciding which local consistency conditions, if any, still need to ...

• Type: Conference
• Year: 1994
• Where: AAAI
• Authors: Peter van Beek
• Keywords: AAAI 1994, Constraint Network, Intelligent Agents, Local Consistency, Local Consistency Conditions