On fuzzy probability theory
The existence of a joint observable of a finite family of observables (with values in a space of fuzzy sets) was proved by \textit{S. Gudder} [Demonstr. Math. 31, 235--254 (1998; Zbl 0952.60002); Found. Phys. 30, 1663--1678 (2000)]. The authors generalize this result to infinite families of observables. Using it, they prove the weak law of large numbers and the central limit theorem. Special attention is paid to the interplay between observables and the less general notion of random variable.
scientific article; zbMATH DE number 1784362