Yves Moinard Mesure de plausibilité pour le raisonnement par défaut , RFIA 2004 (Reconnaissance des Formes et Intelligence Artificielle) , Toulouse , Vol. 1 , 217--226 , jan , 2004 , Document Abstract Friedman and Halpern have introduced the notion of inference by plausibility, which encompasses various approaches of default reasoning. However, their version is somehow limited in its expressivity. A natural modification of the original definition gives a formalism which can encompass a greater number of % previously known formalisms. In particular, all the examples studied in the paper of Friedman and Halpern can be expressed in this variant also, and other formalisms, which escaped the original version, fall prey to the new one. This confirms the interest of the notion of plausibility measures, the only difference being a small simplification in the definitions. While giving these results, we make a comparative study of the properties satisfied by the original version and those satisfied by the new one. Thus, we complete also the list of the known properties of the original inference by plausibility. This web site is maintained by René Quiniou using the Weave system from the Caravel project: http://www-caravel.inria.fr. Last modification: 10-07-2011 09:54:25 Version française