Ressenyes

Obra ressenyada: Allan J. KUETHE, ; Juan F. MARCHENA (eds.), Soldados del Rey: El ejército borbónico en América colonial en vísperas de la independencia. Castelló de la Plana: Publicacions de la Universitat Jaume I, 2005

Measuring Local Aggregate House Prices

This study evaluates the ability of a range of popular aggregate house price indexes to predict house prices out-of-sample at the transaction level for a small geographic area. The analysis particularly addresses the utility of spatial econometric methods. The results suggest that spatial econometric methods, which more explicitly consider the spatial aspects of observed house prices, provide better predictive accuracy as compared to more traditional estimation techniques, such as the repeat sales index, a hybrid repeat sales-hedonic price index, and hedonic price models estimated through least squares. The conclusions are drawn from a sample of 38,984 single-family residential real estate transactions for the city of Milwaukee, Wisconsin over the years 2002-2008.House price index; Spatial econometrics; Forecast evaluation

Consumer Willingness-to-Pay for Fresh Pork Attributes

A survey was used to gauge consumer preferences toward four fresh pork attributes: juiciness, tenderness, marbling, and leanness. The survey elicited consumer willingness-to-pay a premium for an improvement in these attributes. Approximately one-half of the respondents were willing to pay some premium for the attributes of juiciness, leanness, and tenderness. The average premium size ranged from $0.20/lb. for marbling to$0.37/lb. for tenderness. Neither the choice of a certifying agency nor the use of a cheap talk script influenced premium levels.pork attributes, pork markets, willingness to pay, Agribusiness, Marketing,

Evaluating the Dynamic Nature of Market Risk

This study examines the systematic risk present in major crops for the United States and three corn-belt states. An index of commodities is used in conjunction with cash receipts to generate dynamic estimates of the systematic risk for each crop and state. In our study, we find that beta estimates from a time varying parameter model (FLS) and OLS formulation are substantially different. From our graphs of betas over time, one gains insight into the changing nature of risk and the impact of institutional and macroeconomic events. Systematic risk is shown to increase for most crops over the analyzed period with significant changes in volatility after the collapse of the Bretton Woods Accord.Systematic risk, flexible least squares, single index model, farm policy, macroeconomics, Agribusiness, Agricultural Finance, Consumer/Household Economics, Demand and Price Analysis, Farm Management, Financial Economics, Institutional and Behavioral Economics, Marketing, Risk and Uncertainty,

Ressenyes

Obra ressenyada: Allan J. KUETHE y Kenneth J. ANDRIEN, The Spanish Atlantic World in the Eighteenth Century. War and the Bourbon Reforms, 1713-1796. Nueva York: Cambridge University Press, 2014

Navier-Stokes analysis of turbine blade heat transfer

Comparisons with experimental heat transfer and surface pressures were made for seven turbine vane and blade geometries using a quasi-three-dimensional thin-layer Navier-Stokes analysis. Comparisons are made for cases with both separated and unseparated flow over a range of Reynolds numbers and freestream turbulence intensities. The analysis used a modified Baldwin-Lomax turbulent eddy viscosity mode. Modifications were made to account for the effects of: (1) freestream turbulence on both transition and leading edge heat transfer; (2) strong favorable pressure gradients on relaminarization; and (3) variable turbulent Prandtl number heat transfer. In addition, the effect of heat transfer on the near wall model of Deissler is compared with the Van Driest model

Delta wing flutter based on doublet lattice method in NASTRAN

The subsonic doublet-lattice method (DLM) aeroelastic analysis in NASTRAN was successfully applied to produce subsonic flutter boundary data in parameter space for a large delta wing configuration. Computed flow velocity and flutter frequency values as functions of air density ratio, flow Mach number, and reduced frequency are tabulated. The relevance and the meaning of the calculated results are discussed. Several input-deck problems encountered and overcome are cited with the hope that they may be helpful to NASTRAN Rigid Format 45 users

Effects of unsteady free stream velocity and free stream turbulence on stagnation point heat transfer

The combined effects of transient free stream velocity and free stream turbulence on heat transfer at a stagnation point over a cylinder situated in a crossflow are studied. An eddy diffusivity model was formulated and the governing momentum and energy equations are integrated by means of the steepest descent method. The numerical results for the wall shear stress and heat transfer rate are correlated by a turbulence parameter. The wall friction and heat transfer rate increase with increasing free stream turbulence intensity

The influence of jet-grid turbulence on heat transfer from the stagnation region of a cylinder in crossflow

The effect of high-intensity turbulence on heat transfer from the stagnation region of a circular cylinder in crossflow was studied. The work was motivated by the desire to be able to more fully understand and predict the heat transfer to the leading edge of a turbine airfoil. In order to achieve high levels of turbulence with a reasonable degree of isotropy and homogeneity, a jet-injection turbulence grid was used. The jet grid provided turbulence intensities of 10 to 12 percent, measured at the test cylinder location, for downstream blowing with the blowing rate adjusted to an optimal value for flow uniformity. Heat transfer augmentation above the zeroturbulence case ranged from 37 to 53 percent for the test cylinder behind the jet grid for a cylinder Reynolds number range of 48,000 to 180,000, respectively. The level of heat transfer augmentation was found to be fairly uniform with respect to circumferential distance from the stagnation line. Stagnation point heat transfer results (expressed in terms of the Frossling number) were found to be somewhat low with respect to previous studies, when compared on the basis of equal values of the parameter Tu Re(1/2), indicating an additional Reynolds number effect as observed by previous investigators. Consequently, for a specified value of Tu Re(1/2), data obtained with a relatively high turbulence intensity will have a lower value of the Frossling number

The Inconvenience Cost: A Portfolio Approach to Non-Convergence Between Cash and Futures Prices

Cash and futures prices should reach equality, or converge, upon contract maturity. Traders can impose convergence during the delivery month through arbitrage behavior: either making or taking delivery on futures contracts. If convergence is not predictable, a futures market fails to provide a clear storage signal to potential inventory holders and reduces the attractiveness of hedging. Recent convergence problems in domestic commodity markets demonstrate the existence of persistent, significant arbitrage opportunities over the second half of the last decade. Yet, terminal elevator operators—perhaps the only participants with the capacity to do so—have not arbitraged away these riskless returns by making enough deliveries. This model demonstrates conditions under which a profit maximizing warehouseman foregoes available arbitrage. We find that making delivery involves substantial opportunity costs, which stem from the loss of managerial control over warehouse space. We refer to the inconvenience of losing such control as the inconvenience cost.Convergence, Arbitrage, Portfolio Theory, Storage, Agricultural Finance, Financial Economics, Risk and Uncertainty, G11, D21, Q14,