Refinements of the CIFF Procedure

Abductive Logic Programming (ALP) combines abductive reasoning with logic programming. In recent work [2], we have introduced a new proof procedure for ALP which we call CIFF. Our procedure extends the IFF procedure of Fung and Kowalski [3] by integrating ALP with constraint solving and by relaxing the restrictions on allowed inputs for which the procedure can operate correctly. CIFF has been applied successfully in the context of multiagent systems. An implementation of the procedure is available at http://www.doc.ic.ac.uk/∼ue/ciff/. In this extended abstract, we summarise several recent refinements of the CIFF procedure. After giving a brief introduction to ALP and CIFF in the next section, we firstly indicate how to extend CIFF with negation as failure and then discuss a number of improvements to the implementation of the procedure, pertaining to both optimisation and usability issues.