Many materials, including leaves, water, plastic, and chrome exhibit specular reflections. It seems reasonable that the visual system can somehow exploit specular reflections to recover three-dimensional (3D) shape. Previous studies (e.g., J. T. Todd & E. Mingolla, 1983; J. F. Norman, J. T. Todd, & G. A. Orban, 2004) have shown that specular reflections aid shape estimation, but the relevant im...

This paper addresses the problem of reducing the effects of wavefront distortions in ground-based telescopes within a "Modal-Control" framework. The proposed approach allows the designer to optimize the Youla parameter of a given modal controller with respect to a relevant adaptive optics performance criterion defined on a "sampled" frequency domain. This feature makes it possible to use turbul...

This paper endeavors to develop a modern theoretical underpinning of Friedrich August von Hayek’s business-cycle theory as published during the Great Depression in his book Prices and Production. According Hayek, economic cycles are caused by monetary shocks, which distort relative-price schedule across sectors. Possible consequences these price distortions, also called “Cantillon effects,” inc...

A salient feature of developing economies is the coexistence of a modern commercial sector alongside a traditional subsistence sector-the dual economy. The apparent differences in productivity between sectors imply substantial losses in aggregate productivity. Existing theories of the dual economy rely on exogenous price distortions, and cannot explain why or if these distortions evolve over th...

We study monetary and fiscal policy games in a dynamic sticky price economy where monetary policy sets nominal interest rates and fiscal policy provides public goods financed with distortionary labor taxes. We compare the Ramsey outcome to non-cooperative policy regimes where one or both policymakers lack commitment power. Absence of fiscal commitment gives rise to a public spending bias, while...

2/9/06 2:08:34 PM Health savings accounts, or HSAs, are a new health insurance option that became available in 2004. HSAs couple a tax-preferred savings account (the HSA) with high-deductible health insurance. Enrollees or their employers, or both, make tax-free contributions to the HSA. Enrollees use the funds in their HSAs to purchase medical care until they reach their deductibles. At that p...

This paper formulates a stylized New Keynesian model in which each individual firm can select the frequency of its price adjustments, and we demonstrate that the endogeneity of the contract structure has a dramatic impact on the magnitude of the aggregate effects of steady-state inflation. We start by analyzing the exact nonlinear properties of a benchmark economy with exogenous contract durati...

Several recent demonstrations using visual adaptation have revealed high-level aftereffects for complex patterns including faces. While traditional aftereffects involve perceptual distortion of simple attributes such as orientation or colour that are processed early in the visual cortical hierarchy, face adaptation affects perceived identity and expression, which are thought to be products of h...