Various kinds of interactive addition of fuzzy numbers, application to decision analysis in presence of linguistic probabilities

After a brief recall of possibility theory and of the concept of interactivity, new results concerning different kinds of addition of fuzzy numbers are given (to introduce these additions, no reference to the extension principle is needed). As an illustration, the application of one of these results to a problem (which was unsolved until now) of decision-making in presence of linguistic probabilities is presented.