Most Constrained First
Short clauses are most constraining
- (A B) rules out 1/4 of all solutions
- (A B C D E) only rules out 1/32 of all solutions
Take account only of shortest clauses
- e.g. shortest clause in a problem may be of length 2
Several variants on this idea
- first occurrence in shortest clause
- most occurrences in shortest clauses (usually many such)
- first occurrence in all positive shortest clause