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Using Branch-and-Bound in an Uncertain World

So far, we have modified the solution synthesis algorithms to use maximally interacting circles of variables in order to exploit their disambiguating power as early as possible. Combined with CSP techniques, these algorithms give fast and completely reliable answers to simplified computational semantic problems. The difficulty is that these problems are simplified. The constraints used in the example above used yes-no constraints. In computational semantics, however, semantic constraints must be used only as tendencies, not sure-and-fast answers. Therefore, for computational semantics, bare CSP techniques are not that helpful.gif In this section, we will demonstrate that branch-and-bound techniques can be combined with solution synthesis to overcome this problem. We will see that the circles created above to aid constraint satisfaction are also optimal with regard to branch-and-bound techniques.





Steve Beale
Tue Oct 1 10:21:38 MDT 1996