197,259 research outputs found
Empirical Tests of the Refutable Implications of Expected Utility Maximization under Risk
No full textThe curvature properties of the indirect utility function imply a set of refutable implications in the form of comparative static results and symmetric relations for the competitive firm operating under uncertainty. These hypotheses, first derived and empirically tested under output price uncertainty by Saha and Shumway (1998), are extended in this paper to the more general case of both price and quantity uncertainty and result in an important theoretical finding. Empirical tests using a panel of state-level observations fail to reject most refutable hypotheses under output price and output quantity risk, but symmetry conditions implied by a twice-continuously-differentiable indirect utility function are rejected. Two restrictive risk preference hypotheses are also rejected. At individual observations, data were consistent with most of the hypotheses implied by individual states acting as though they were expected utility-maximizing firms.indirect utility function, refutable implications, risk and uncertainty, Risk and Uncertainty,
Adding challenge to performance-based tests of walking - The walking InCHIANTI toolkit (WIT)
No full textObjective: In this report, we provide a detailed description of and reproducibility data on the 14 performance-based tests of lower limb function included in the Walking InCHIANTI Toolkit, which were designed to mimic challenging situations that are encountered while walking in daily life. Design: Five women and five men were randomly selected from each of the age strata, 65-74, 75-84, and >= 85 yrs, among those who received a functional evaluation in the Greve site at the second InCHIANTI study follow-up (total n = 30). Walking tests were administered twice at 2-wk intervals. Analyses were aimed at assessing reproducibility of the Walking InCHIANTI Toolkit components and the existence of a learning effect. Results: Performance remained stable for eight walking tests and slightly but significantly improved for the 25-cm narrow-path walk, 7-m usual-pace, 7-m obstacle normal light, 7-m holding a package, and 7-m talking while walking tests. Test-retest reliability was in general very high, with 11 of 14 (79%) of the intraclass; correlation coefficient values > 0.80 and all except one (7-m holding a package) > 0.75. Conclusion: The walking tests included in the Walking InCHIANTI Toolkit show very good medium-term reproducibility and modest learning effect. Administering components of the Walking InCHIANTI Toolkit may help in the understanding of the effect of challenges encountered in daily life on walking performance
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
Firm level beef supply : a simulation and linear programming application in East Texas
No full textVita.Beef production is the foremost agricultural activity in East Texas. Although production practices vary, the cow-calf enterprise dominates. Much of the land is used for production of forages that vary from native grasses to tame pastures. But high production costs are causing producers to search for more profitable combinations of forage and livestock systems. To achieve this goal, they need better and more accurate information on forage and livestock production relationships. The overall objective of this study is to identify the most profitable forage and beef systems, both under certainty and uncertainty, for an experimental cow-calf farm in East Texas. Specific objectives addressed are: (a) to generate reliable input-output coefficients for beef calves, stockers, and slaughter cattle for this farm, (b) to determine the effects on beef production of simultaneous changes in quality and quantity of forages, of different calving seasons, and of different cattle enterprises, (c) to analyze effects of changes in product and factor prices on the firm's supply of beef in the short and long run, and (d) to develop expected profit-risk frontiers. Three models, a biological beef cattle simulation model (the TAMU model) and two linear programming models (the acreage model and the economic model), are interfaced to achieve the objectives of this study. Given four livestock enterprises (cow-calf, Stocker, drylot-finishing, and forage-finishing), three alternative forage systems (Coastal bermudagrass, Coastal bermudagrass overseaaed with rye-ryegrass, and common bermudagrass overseeded with crimson clover-ryegrass), and four levels of winter feeding (ad lib and 80 percent, 60 percent, and 40 percent of ad lib), the TAMU model is used to simulate beef cattle production. Using the simulated results as model inputs, the acreage model is applied to determine for each of the above the least cost acreage of a particular forage, purchased hay and supplements required to support the simulated herd. Then the results generated by these two models are used as data in the economic model. The economic model is used (a) to solve for the optimal livestock enterprises, forage systems, and winter feed stress level, (b) to derive firm-level beef supply response under certainty, and (c) to develop expected E-A frontiers under uncertainty..
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
A linear CET commodity supply response model for thirteen agricultural field crops in the U.S
No full textVita.The objective of this study is to estimate short run supply responsiveness, including interactions, among thirteen major U.S. field crops. Although major emphasis is on response to price changes, the effects of risk and commodity programs on production decisions are also examined. After initial hypothesis testing, remaining attention is focused on sensitivity of conclusions to changes in model specification. Powell and Gruen's constant elasticity of transformation (CET) linear commodity supply model is adapted and applied to the estimation of supply response for the years 1947 and 1975. The CET commodity supply model is utilized because it reduces the number of price parameters requiring estimation in a fully specified multiproduct supply model. This reduction is possible because (a) the commodity price parameters (i.e., elasticities of transformation) are symmetric and (b) each commodity supply equation is homogeneous of degree zero in commodity prices. The theoretical derivation of the CET commodity supply model is expanded in this study. Risk is added as a behavioral variable. The definition of the shift function is enlarged to include input level, technology, government commodity policies, and weather. Input supply response is included in the model to permit a more accurate estimation of short run commodity supply response
Adaptive planning for Texas cattle producers facing uncertain prices
No full textVita.Cattle producers typically react to cyclical prices by increasing the size of the breeding herd as price increases and decreasing it as price decreases. Current decisions to cull and/or replace cows are based on such data as current and expected prices, the financial condition of the firm, and the amount of unused resources available. The decision process is a dynamic problem of pursuing not only a goal for the current planning period, but goals for future periods as well. One objective of this thesis is to develop a detailed simulation model of a commercial Texas cattle farm The model can be sued experimentally to examine the effects of various decisions on a wide range of farm goals. A second objective is to interface the model with an optimizing algorithm to determine optimal annual replacement and culling decisions given various qualities of price forecasts. The assumed goal of the firm is to maximize discounted net revenue over an indefinite period of time. A ten-year rolling planning horizon is used to permit the firm to annually revise policies as it moves through time. The objective function maximized for each ten-year planning horizon is the sum of the expected present value of net revenue earned during the ten years and the present value of an annuity of expected annual net revenue after the tenth year. An adaptive plan emerges from the set of optimal first-year policies taken from a sequence of planning horizons. The adaptive plan is itself not an optimal plan since it does not maximize an objective function. Three types of price forecasts are used with the optimizing routine, (1) perfect forecasts based on actual prices, (2) forecasts based on the expectation that current prices will continue unchanged in the future, and (3) forecasts based on the expectation that future prices will have the same period and amplitude as recent price cycles. It is hypothesized that variable replacement and culling policies, sensitive to price expectations, produce a higher present value of net revenue over a ten-year period than policies calling for constant culling and replacement rates..
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