id: 06049893 dt: j an: au: Majlender, Péter ti: A note on the convexity assumption of possibilistic correlation. so: Appl. Math. Lett. 25, No. 4, 672-675 (2012). py: 2012 pu: Elsevier Science Ltd. (Pergamon), Oxford la: EN cc: 62 ut: joint possibility distribution; possibilistic correlation coefficient ci: li: doi:10.1016/j.aml.2011.08.023 ab: Summary: In 2005, Carlsson, Fullér and Majlender introduced a measure of possibilistic correlation of fuzzy numbers A and B by their joint possibility distributionC as an average degree of interaction between the $γ$-level sets of A and B as compared to their individual dispersions. They proved that this possibilistic correlation coefficient can never exceed 1 in absolute value, if all $γ$-level sets of the joint possibility distribution C are convex. In this communication, we shall formulate a special class of joint possibility distributions with non-convex $γ$-level sets, for which the correlation coefficient can take values outside the interval [-1,1]. In particular, this result will show that the assumption about the convexity of the level sets of C is essential for the possibilistic correlation to be bounded by the interval [-1,1]. rv: