to evaluate the influence of core thickness and fabrication stages on the marginal accuracy of ips e.max press crowns.twenty ips e.max press crowns, 1.5mm thick, were fabricated on metal dies. the crowns had two different core thicknesses, 0.8mm for group a and 1mm for group b, ten for each group. marginal gap was measured after each stage of core fabrication, veneering and glaze firing. the sp...

Conventional hedonic analysis measures willingness to pay for attributes on the basis of marginal fixed costs. We argue that in many cases variable costs are also affected by these attributes and that this should be taken into account. We develop a simple model to show that the marginal willingness to pay for a quality attribute has to be equal to the full marginal cost, which includes marginal...

It has recently been shown that incorporating “keeping up with the Joneses”preferences into a prototypical two-ability-type optimal nonlinear income tax model leads to higher marginal tax rates for both types of agents. In particular, the high-skill type faces a positive marginal tax rate, rather than zero as in the conventional case. In this paper, agents’utility functions are postulated to ex...

Knowledge about the potential spatial dynamics of species is important. Already in 1922, the American ornithologist Joseph Grinnell (Grinnell 1922) noted that in order to understand the population consequences of dispersal, its role in the stochastic nature of rare longdistance movements and the interplay between innate and environmental factors in triggering dispersal, have to be known. Furthe...

This paper develops a political economy model that is consistent with the fact that democracies have a preference for increasing marginal tax rates on income. We present a model in which there is an exogenous set of political parties with preferences over the set of admissible tax schedules. This set contains virtually any increasing and piecewise linear continuous function. Each party decides ...

We consider an environment in which agents’ skills are private information and follow arbitrary stochastic processes. We prove that it is typically Pareto optimal for an individual’s marginal benefit of investing in capital to exceed his marginal cost of doing so. This wedge is consistent with a positive tax on capital income. We also prove that it is Pareto optimal for the marginal rate of sub...

the main objective of this study was to investigate the economic efficiency of investment in sugar beet breeding research in iran. the required information including the value and cost of sugar beet production in 2010 and the budget allocated to the sugar beet breeding research were obtained from the office of statistics and information technology of ministry of jihad-e-agriculture and agricult...