In this paper, we show that coherent upper and lower previsions as well as coherent risk measures are only meaningful under the assumption that one starts with initial wealth being constantly 0. This implies at least for coherent upper and lower previsions a correction of their interpretation,...

A class of contribution values for pairs of random variables is introduced as a technical tool for the problem how the risk capital needed for a portfolio of random activities should be allocated to its components. The well known allocation model with expected shortfall as corresponding risk...