InfOCF-Web provides implementations of system P and system Z inference, and of inference relations based on c-representation with respect to various inference modes and different classes of minimal models. It has an easy-to-use online interface for computing ranking models of a conditional knowledge R, and for answering queries and comparing inference results of nonmonotonic inference relations induced by R.

While the axiomatic system P is an important standard for plausible nonmonotonic reasoning, inference relations obtained from system Z or from c-representations have been designed which go beyond system P. In this paper, we propose the new concept of weakly skeptical inference that properly extends the recently introduced skeptical c-inference, but avoids disadvantages of a too liberal credulous inference. We extend the concepts of skeptical, weakly skeptical, and credulous c-inference by taking preferred models obtained from different minimality criteria into account. We illustrate the usefulness of the obtained inference relations, show that they fulfill various desirable properties, and elaborate on their interrelationships.