7,111 research outputs found
High pressure cosmochemistry applied to major planetary interiors: Experimental studies
The measurement of equilibria in binary fluid-solid systems in diamond anvil cells, represents a major advance of the art of high-pressure experimentation. Vibrational spectroscopy, direct visual observations, and X-ray diffraction crystallography of materials confined in externally heated cells are the primary experimental probes being used. Adiabats in these systems are being measured in order to constrain models of heat flow in these bodies and to detect phase transitions by thermal anomalies. Other studies are directed toward interpreting high pressure reactions in these systems that are suggested by shockwave measurements, and developing methods for reaching high temperatures and high pressures of planetary interest in diamond cells. The overall objective of this project is to determine the properties of the H2-He-H2O-HN3-CH4 system and related small-molecule systems that are needed to constrain theoretical models of the interiors of the major planets
Competition Leverage: How the Demand Side Affects Optimal Risk Adjustment
We study optimal risk adjustment in imperfectly competitive health insurance markets when high-risk consumers are less likely to switch insurer than low-risk consumers. First, we find that insurers still have an incentive to select even if risk adjustment perfectly corrects for cost differences among consumers. Consequently, the outcome is not efficient even if cost differences are fully compensated. To achieve first best, risk adjustment should overcompensate for serving high-risk agents to take into account the difference in mark- ups among the two types. Second, the difference in switching behavior creates a trade off between efficiency and consumer welfare. Reducing the difference in risk adjustment subsidies to high and low types increases consumer welfare by leveraging competition from the elastic low-risk market to the less elastic high-risk market. Finally, mandatory pooling can increase consumer surplus even further, at the cost of efficiency.health insurance;risk adjustment;imperfect competition;leverage
Selective Contracting and Foreclosure in Health Care Markets
We analyze exclusive contracts between health care providers and insurers in a model where some consumers choose to stay uninsured. In case of a monopoly insurer, exclusion of a provider changes the distribution of consumers who choose not to insure. Although the foreclosed care provider remains active in the market for the non-insured, we show that exclusion leads to anti-competitive effects on this non-insured market. As a consequence exclusion can raise industry profits, and then occurs in equilibrium. Under competitive insurance markets, the anticompetitive exclusive equilibrium survives. Uninsured consumers, however, are now not better off without exclusion. Competition among insurers raises prices in equilibria without exclusion, as a result of a horizontal analogue to the double marginalization effect. Instead, under competitive insurance markets exclusion is desirable as long as no provider is excluded by all insurers.health insurance;uninsured;selective contracting;exclusion;foreclosure;anti-competitive effects
Competition for Traders and Risk
Abstract: The financial crisis has been attributed partly to perverse incentives for traders at banks and has led policy makers to propose regulation of banksā remuneration packages. We explain why poor incentives for traders cannot be fully resolved by only regulating the bankās top executives, and why direct intervention in trader compensation is called for. We present a model with both trader moral hazard and adverse selection on trader abilities. We demonstrate that as competition on the labour market for traders intensifies, banks optimally offer top traders contracts inducing them to take more risk, even if banks fully internalize the costs of negative outcomes. In this way, banks can reduce the surplus they have to offer to lower ability traders. In addition, we find that increasing banksā capital requirements does not unambiguously lead to reduced risk-taking by their top traders.optimal contracts;remuneration policy;imperfect competition;financial institutions;risk
Superintendents and Professional Development: Voices from the Field
The primary task of the educational leader is to assure high quality learning environments for all students. Research (Gordon, 2004; Sparks, 2007) supports the proposition that effective professional development contributes to instructional improvement by building educator capacity. Much of the research on professional development focuses in principal leadership in improving instruction (Blase & Blase, 2004). But district level administrators, especially the superintendent of schools, also have a role to play in school improvement. Standards for the preparation of school leaders specify competencies for superintendents that include the design and implementation of professional development programs based on sound research, best practices, district-and school-level data, and other contextual information (National Policy Board, 2002). The National Staff Development Council\u27s Standards (2001) also describe a comprehensive set of activities to improve student learning that apply to both campus and district level personnel. But while the research on the instructional leadership role of principals is extensive, comparatively little is said about how superintendents meet their own responsibilities in this area (Dufour, 2000; Hirsch, 2009; Firestone, Manquin, & Martinez, 2005)
High pressure cosmochemistry applied to major planetary interiors: Experimental studies
The overall goal of this project is to determine properties of the H-He-C-N-O system, as represented by small molecules composed of these elements, that are needed to constrain theoretical models of the interiors of the major planets. Much of our work now concerns the H2O-NH3 system. This project is the first major effort to measure phase equilibria in binary fluid-solid systems in diamond anvil cells. Vibrational spectroscopy, direct visual observations, and X-ray crystallography of materials confined in externally heated cells are our primary experimental probes. We also are collaborating with the shockwave physics group at Lawrence Livermore Laboratory in studies of the equation of state of a synthetic Uranus fluid and molecular composition of this and other H-C-N-O materials under planetary conditions
The Hurricane Mountain Formation Melange and unconfomably overlying Lower to Middle Ordovician volcanics, Brassua Lake and Moosehead Lake Quadrangles
New England Intercollegiate Geological Conference Guidebook for field trips in The Greenville - Millinocket Regions, North Central Maine, October 7-9, 1983: Trip B-
Tectonic and Metamorphic History of the Lower Devonian Rocks in the Carrabasset Valley North of Kingfield, Maine
Guidebook for field trips in the Rangeley Lakes - Dead River Basin region, western Maine: 62nd annual meeting October 2, 3, and 4, 1970: Trip A-
Shortest Path across Stochastic Network with Correlated Random Arcs
This paper introduces a new approach to identify the shortest path across a stochastic network with correlated random arcs utilizing nonparametric samples of arc lengths. This approach is applied to find optimal aircraft routes that minimize expected fuel consumption for a given airspeed utilizing predicted wind output from NWP ensemble models. Results from this new methodology are then compared to the current fuel minimization route planning method that utilizes deterministic NWP wind data for arc lengths. Comparisons are also made to other previously proposed alternative fuel minimization methodologies that utilize mean and median wind data calculated from NWP ensemble wind data
- ā¦