On a perturbed dual risk model with dependence between inter-gain times and gain sizes
ABSTRACTThe dual risk model may be used to model the revenue process of a company with constant expense rate and occasional gains. In this paper, we consider a dual risk model with both inter-gain times and expense rates depending on the size of previous gain. Also, we assume the process is perturbed by a Brownian motion. Exact solutions for the Laplace transform and the first moment of the time to ruin with arbitrary gain-size distribution are obtained. Applications with numerical illustrations are provided to examine the impacts of the dependence structure and perturbation.
We describe preliminary results from an effort to quantify the uncertainties in parton distribution functions and the resulting uncertainties in predicted physical quantities. The production cross section of the $W$ boson is given as a first example. Constraints due to the full data sets of the CTEQ global analysis are used in this study. Two complementary approaches, based on the Hessian and the Lagrange multiplier method respectively, are outlined. We discuss issues on obtaining meaningful uncertainty estimates that include the effect of correlated experimental systematic uncertainties and illustrate them with detailed calculations using one set of precision DIS data.