In this paper, we consider portfolio selection problem in which security returns are regarded as fuzzy variables rather than random variables. We first introduce a concept of absolute deviation for fuzzy variables and prove some useful properties, which imply that absolute deviation may be used to measure risk well. Then we propose two mean-absolute deviation models by defining risk as abs...

69 ABSTRACT PURPOSE: To report the incidence of anisocoria after unilateral excimer laser photorefractive kera-tectomy (PRK) for myopia and subsequent cortico-steroid therapy in a retrospective and prospective study and to explore possible etiologies. METHODS: The horizontal pupil diameter was determined in 6 patients (6 eyes) at 21.8 ± 12.6 months after unilateral wide-field excimer laser PRK ...

A Markowitz-type portfolio selection problem is to minimize a deviation measure of portfolio rate of return subject to constraints on portfolio budget and on desired expected return. In this context, the inverse portfolio problem is finding a deviation measure by observing the optimal mean-deviation portfolio that an investor holds. Necessary and sufficient conditions for the existence of such ...