classical explicit finite difference schemes are unsuitable for the solution of the famous black-scholes partial differential equation, since they impose severe restrictions on the time step. furthermore, they may produce spurious oscillations in the solution. we propose a new scheme that is free of spurious oscillations and guarantees the positivity of the solution for arbitrary stepsizes. the...

In an interesting article Wieteke van Dijk and colleagues argue that societal developments and values influence the practice of medicine, and thus can result in both medicalisation and overdiagnosis. They provide a convincing argument that overdiagnosis emerges in a social context and that it has socially constructed implications. However, they fail to show that overdiagnosis per se is socially...

Despite the growing recognition among researchers of the potentially important role that interpersonal affect plays in performance appraisals, it is not clear whether the effect of interpersonal affect is real or attributable to unobserved ratee characteristics. Using a fixed effects model, I find that the effect of interpersonal affect on ratings is significant and independent of unobserved ra...

Most physicians believe that to provide the best possible care to their patients, they must commit to continuous learning. For the most part, it appears the learning activities currently available to physicians do not provide opportunities for meaningful continuous learning. At the same time there have been increasing concerns about the quality of health care, and a variety of groups within org...