bstract. We present a modification of the new edge-directed inerpolation method that eliminates the prediction error accumulation roblem by adopting a modified training window structure, and exending the covariance matching into multiple directions to suppress he covariance mismatch problem. Simulation results show that the roposed method achieves remarkable subjective performance in reserving ...

The purpose of this article is to provide students and researchers entering the field of aging studies with an introduction to the evolutionary theories of aging, as well as to orient them in the abundant modern scientific literature on evolutionary gerontology. The following three major evolutionary theories of aging are discussed: 1) the theory of programmed death suggested by August Weismann...

To quantify the force of selection, Hamilton [Hamilton, W. D. (1966) J. Theor. Biol. 12, 12-45] derived expressions for the change in fitness with respect to age-specific mutations. Hamilton's indicators are decreasing functions of age. He concluded that senescence is inevitable: survival and fertility decline with age. I show that alternative parameterizations of mutational effects lead to ind...

Analysis of a recent mutation accumulation (MA) experiment has led to the suggestion that as many as one-half of spontaneous mutations in Arabidopsis are advantageous for fitness. We evaluate this in the light of data from other MA experiments, along with molecular evidence, that suggest the vast majority of new mutations are deleterious.

This paper examines the role of education as causal channel through which growing up poor affects the individual’s economic outcomes as an adult. We contribute to the literature on intergenerational transmission in two ways. First, we apply a potential outcomes approach to quantify the impact of experiencing poverty while growing up and we provide a sensitivity analysis on the unobserved parent...

This paper introduces a computational model of online collaborative learning system and investigates how the heterogeneity of opportunity cost among users initiates a vicious cycle of accumulation of unnecessary duplicate postings and eventually the system shuts down. Further examination explores how deterring newcomers improves collaborative learning system efficiency by reducing unnecessary d...

Introduction Conclusions References

We analyze the influence of tax progression on optimal investment policy and its value. We show that three possible optimal regimes arise, depending on the nature of the tax policy. If the exogenously given progression threshold lies between the optimal capital stocks in the case of higher and lower marginal profit taxes, then the optimal investment policy is independent of profit tax rates. Bu...

We analyze the impact of tax progression on optimal investment policy and its value by first demonstrating that optimal investment policy maximizes the value of the firm and the rate at which it is growing as a function of operating capital stock. Then we show that three possible optimal regimes arise depending on the nature of tax policy. If the exogenously given progression threshold lies bet...