We consider a class of Markovian risk models in which the insurer collects premiums at rate c1 (c2) whenever the surplus level is below (above) a constant barrier level b. We derive the Laplace­Stieltjes transform (LST) of the distribution of the time to ruin as well as the LST (with respect to time) of the joint distribution of the time to ruin, the surplus prior to ruin, and the deficit at ru...

In open conduit volcanoes, volatile-rich magma continuously enters into the feeding system nevertheless the eruptive activity occurs intermittently. From a practical perspective, the continuous steady input of magma in the feeding system is not able to produce eruptive events alone, but rather surplus of magma inputs are required to trigger the eruptive activity. The greater the amount of surpl...

Changes in total surplus and deadweight loss are traditional measures of economic welfare. We propose necessary and sufficient conditions for rationalizing consumer demand data with a quasilinear utility function. Under these conditions, consumer surplus is a valid measure of consumer welfare. For nonmarketed goods, we propose necessary and sufficient conditions on market data for efficient pro...

This paper develops numerical methods for finding optimal dividend pay-out and reinsurance policies. A generalized singular control formulation of surplus and discounted payoff function is introduced, where the surplus is modeled by a regime-switching process subject to both regular and singular controls. To approximate the value function and optimal controls, Markov chain approximation techniq...

Short-term alterations in dietary carbohydrate (CHO) energy are known to alter whole-body fuel selection in humans, but the metabolic mechanisms remain unknown. We used stable isotope-mass spectrometric methods with indirect calorimetry in normal subjects to quantify the metabolic response to six dietary phases (5 d each), ranging from 50% surplus CHO (+50% CHO) to 50% deficient CHO (-50% CHO),...

This paper examines the performance of property and liability reinsurance companies in the United States. It shows that these reinsurers have higher mean values than primary insurers in the following financial ratios: net operating income to net premium earned (NOI/PE), yield on invested assets (YIA), and loss reserves to net premium written (LR/NPW). Primary insurers, on the other hand, have h...