On Random Ordering Constraints

Abstract. Ordering constraints are analogous to instances of the satisfiability problem in conjunctive normalform, but instead of a boolean assignment we consider a linear ordering of the variables in question. A clause becomes true given a linear ordering iff the relative ordering of its variables obeys the constraint considered. The naturally arising satisfiability problems are NP-complete for many types of constraints. The present paper seems to be one of the first looking at random ordering constraints. Experimental evidence suggests threshold phenomena as in the case of random k-SAT instances and thus natural problems to be proved. We state some basic observations and prove two results: First, random instances of the cyclic ordering and betweenness constraint (definition see Subsection

• Type: Conference
• Year: 2009
• Where: CSR
• Authors: Andreas Goerdt
• Keywords: CSR 2009, Linear Ordering, Ordering Constraints, Random Ordering Constraints, Theoretical Computer Science