1,707 research outputs found
Microcosm study of arsenic fate in Mahomet Aquifer sediment and groundwater
Includes bibliographical references"Final Report March 29, 2006.""MTAC Publication TR06-08.
Consumption Correlatedness and Risk Measurement in Economies with Non trade Assets and Heterogeneous Information
The consumption beta theorem of Breeden makes the expected return on any asset a function only of its covariance with changes in aggregate consumption. It is shown that the theorem is more robust than was indicated by Breeden. The theorem obtains even if one deletes Breeden's assumptions that (a) all risky assets are tradable, (b) investors have homogeneous beliefs, (c) other assets can be traded without transactions costs and (d) that all assets have returns which are Ito processes.
A study of the quality of public welfare administration in one district in Massachusetts
Thesis (M.S.)--Boston University, 1946. This item was digitized by the Internet Archive
Estimating the Continuous Time Consumption Based Asset Pricing Model
The consumption based asset pricing model predicts that excess yields are determined in a fairly simple way by the market's degree of relative risk aversion and by the pattern of covariances between percapita consumption growth and asset returns. Estimation and testingis complicated by the fact that the model's predictions relate to the instantaneous flow of consumption and point-in-time asset values, but only data on the integral or unit average of the consumption flow is available. In our paper, we show how to estimate the parameters of interest consistently from the available data by maximum likelihood. We estimate the market's degree of relative risk aversion and the instantaneous covariances of asset yields and consumption using six different data sets. We also test the model's overidentifying restrictions.
A new look at an old virus: patterns of mutation accumulation in the human H1N1 influenza virus since 1918
BACKGROUND: The H1N1 influenza A virus has been circulating in the human population for over 95 years, first manifesting itself in the pandemic of 1917–1918. Initial mortality was extremely high, but dropped exponentially over time. Influenza viruses have high mutation rates, and H1N1 has undergone significant genetic changes since 1918. The exact nature of H1N1 mutation accumulation over time has not been fully explored. METHODS: We have made a comprehensive historical analysis of mutational changes within H1N1 by examining over 4100 fully-sequenced H1N1 genomes. This has allowed us to examine the genetic changes arising within H1N1 from 1918 to the present. RESULTS: We document multiple extinction events, including the previously known extinction of the human H1N1 lineage in the 1950s, and an apparent second extinction of the human H1N1 lineage in 2009. These extinctions appear to be due to a continuous accumulation of mutations. At the time of its disappearance in 2009, the human H1N1 lineage had accumulated over 1400 point mutations (more than 10% of the genome), including approximately 330 non-synonymous changes (7.4% of all codons). The accumulation of both point mutations and non-synonymous amino acid changes occurred at constant rates (μ = 14.4 and 2.4 new mutations/year, respectively), and mutations accumulated uniformly across the entire influenza genome. We observed a continuous erosion over time of codon-specificity in H1N1, including a shift away from host (human, swine, and bird [duck]) codon preference patterns. CONCLUSIONS: While there have been numerous adaptations within the H1N1 genome, most of the genetic changes we document here appear to be non-adaptive, and much of the change appears to be degenerative. We suggest H1N1 has been undergoing natural genetic attenuation, and that significant attenuation may even occur during a single pandemic. This process may play a role in natural pandemic cessation and has apparently contributed to the exponential decline in mortality rates over time, as seen in all major human influenza strains. These findings may be relevant to the development of strategies for managing influenza pandemics and strain evolution
Injecting New Workforce Leaders in Tourism, Hospitality and Environmental Science: A Community-Engaged Learning and Immersion Class
Tourism, especially nature-based tourism, is a major and growing industry in Maine. Therefore, it is important that colleges and universities graduate leaders into the Maine workforce with specific knowledge of the tourism and hospitality industry and with a connection to the environment in which it is flourishing. To graduate these potential leaders, schools must do a better job at retaining and graduating students from diverse socioeconomic backgrounds. Community-engaged learning, including immersion classes, are a key strategy to increase student persistence in some programs at the University of Southern Maine (USM). Two academic units at USM, the Program in Tourism and Hospitality and the Department of Environmental Science and Policy, collaborate in delivering a colocated intensive immersion class for all new majors. This engagement early in their college career fosters a sense of community among the students and with the industry in which they will work. We argue that this community engagement is a factor contributing to student retention and success in these programs and will help create the creative, resilient, locally active leaders needed to guide sustainable tourism development in Maine
Investigation of the Cape Rosier Zinc-Copper-Lead Mine, Hancock County, Maine
From the introduction: The Bureau of Mines has been investigating deposits of critical and essential minerals in the United Sates and Alaska since 1939. During the fall of 1942, the Bureau of Mines put down nine diamond-drill holes at the Cape Rosier zinc-copper-lead mine in Hancock County, Maine, that aggregated 2,883 feet of bore... This report describes the work done by the Bureau of Mines and presents the data obtained in the two periods of drilling.
Report of Investigations no. 4344 (R. I. 4344)
The Determinants of the Variability of Stock Market Prices
The most familiar interpretation for the large and unpredictable swings that characterize common stock price indices is that price changes represent the efficient discounting of "new information" It is remarkable given the popularity of this interpretation that it has never been established what this information is about. Recent work by Shiller, and Stephen LeRoy and Richard Porter, has shown evidence that the variability of stock price indices cannot be accounted for by information regarding future dividends since dividends just do not seem to vary enough to justify the price movement. These studies assume a constant discount factor. In this paper, we consider whether the variability of stock prices can be attributed to information regarding discount factors (i.e., real interest rates), which are in turn related to current and future levels of economic activity. The appropriate discount factor to be applied to dividends which are received k years from today is the marginal rate of substitution between consumption today and consumption k periods from today, We use historical data on per capita consumption from 1890-1979 to estimate the realized value of these marginal rates of substitution. Theoretically, as LeRoy and C. J. La Civita have also noted independently of us, consumption variability may induce stock price variability whose magnitude depends on the degree of risk aversion.
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