BEYOND THE MODEL SPECIFICATION PROBLEM: MODEL AND PARAMETER AVERAGING USING BAYESIAN TECHNIQUES

The model specification problem is perhaps the Achilles heel of applied econometrics. Rather than test down to a single model as is usually done, we estimate 72 different demand systems and use Bayesian averaging procedures over all 72 systems to generate meta estimates of the parameters (e.g., elasticities) of interest.Research Methods/ Statistical Methods,

AN ANALYSIS OF EXPORT MARKET STRATEGIES AND BARRIERS PERCEPTIONS BY U.S. AGRICULTURAL HVP EXPORTERS

This study identifies barriers perceived by agricultural exporters and examines how these perceptions influence use of export market strategies. Ordered logit models are used to estimate effects of perceived barriers and firm characteristics on export market strategies. The results from these models show that perceptions about import restrictions influence use of diversification of exports across products, competition influences use of competitive export pricing, and overseas product regulations affect product adaptation for export markets.International Relations/Trade,

TWO-STAGE UTILITY MAXIMIZATION AND IMPORT DEMAND SYSTEMS REVISITED: LIMITATIONS AND AN ALTERNATIVE

Two-stage utility maximization theory has been widely used in the literature to estimate import demand for agricultural commodities that are often inputs. This article examines the overlooked conceptual and empirical limitations of applying two-stage utility maximization theory to model the demand for imported commodities that are inputs. A discussion is presented about how the underutilized theory of two-stage profit maximization overcomes these limitations. Also discussed are the conditions under which errors illustration of the two-stage profit maximization procedure is provided.Demand and Price Analysis, International Relations/Trade,

Vibrational testing of optical fiber connector joints

An experimental study was performed to determine the effects of vibration on the propagation of light through SMA- and ST-type fiber-optic connectors. A multimode, fiber-optic link was vibrated from 0 to 10,000 Hz at a constant peak acceleration along the connector transverse and longitudinal axes. All other environmental parameters were ambient. Transfer characteristics through the connection were examined as a function of vibrational frequency using both laser and light-emitting diode (LED) light to illuminate the system. Slight differences in operation between the SMA and ST connectors were observed with no appreciative attenuation as a result of vibration. Vibration did cause the constant-amplitude input light to be modulated in the connector; however, the amplitude of vibration-induced noise was less than 3 standard deviations from the mean

Deep reef fish surveys by submersible on Alderdice, McGrail, and Sonnier Banks in the Northwestern Gulf of Mexico

Submersible surveys at numerous reefs and banks in the northwestern Gulf of Mexico (NWGOM) were conducted as part of the Sustainable Seas Expedition (SSE) during July/August 2002 to identify reef fish communities, characterize benthic habitats, and identify deep coral reef ecosystems. To identify the spatial extent of hard bottom reef communities, the Flower Garden Banks National Marine Sanctuary (FGBNMS) and the U.S. Geological Survey (USGS) mapped approximately 2000 km2 of the Northwestern Gulf of Mexico (NWGOM) continental shelf during June 2002 with high-resolution multibeam bathymetry. Previous investigations conducted on the features of interest (with the exceptions of East and West Flower Garden and Sonnier Banks, accessible by SCUBA) had not been conducted since the 1970s and 1980s, and did not have the use of high-resolution maps to target survey sites. The base maps were instrumental in navigating submersibles to specific features at each study site during the Sustainable Seas Expedition (SSE)—a submersible effort culminating from a partnership between the National Atmospheric and Oceanic Administration (NOAA) and the National Geographic Society (NGS). We report the initial findings of our submersible surveys, including habitat and reef fish diversity at McGrail, Alderdice, and Sonnier Banks. A total of 120 species and 40,724 individuals were identified from video surveys at the three banks. Planktivorous fishes constituted over 87% by number for the three banks, ranging from 81.4% at Sonnier Banks to 94.3% at Alderdice Bank, indicating a direct link to pelagic prey communities, particularly in the deep reef zones. High numbers of groupers, snappers, jacks, and other fishery species were observed on all three features. These sites were nominated as Habitat Areas of Particular Concern (HAPC) by the Gulf of Mexico Fishery Council in March 2004. Data obtained during this project will contribute to benthic habitat characterization and assessment of the associated fish communities through future SCUBA, ROV, and submersible missions, and allow comparisons to other deep reef ecosystems found throughout the Gulf of Mexico and western Atlantic Ocean

A unitary quantum lattice gas algorithm for two dimensional quantum turbulence

Quantum vortex structures and energy cascades are examined for two dimensional quantum turbulence (2D QT) at zero temperature. A special unitary evolution algorithm, the quantum lattice gas (QLG) algorithm, is employed to simulate the Bose-Einstein condensate (BEC) governed by the Gross-Pitaevskii (GP) equation. A parameter regime is uncovered in which, as in 3D QT, there is a short Poincar\'e recurrence time. It is demonstrated that such short recurrence times are destroyed as the nonlinear interaction is strengthened. The similar loss of Poincar\'e recurrence is also reported in 3D QT [1] Energy cascades for 2D QT are considered to examine whether 2D QT exhibits inverse cascades as in 2D classical turbulence. In the parameter regime considered, the spectra analysis reveals no such dual cascades-dual cascades being a hallmark of 2D classical turbulence

EMPIRICAL LIKELIHOOD ESTIMATORS OF THE LINEAR SIMULTANEOUS EQUATIONS MODEL

Information theoretic estimators are specified for a system of linear simultaneous equations, including maximum empirical likelihood, maximum empirical exponential likelihood, and maximum log Euclidean likelihood. Monte Carlo experiments are used to compare finite sample performance of these estimators to traditional generalized method of moments.Research Methods/ Statistical Methods,

Temperature‐dependent transmission extended electron energy‐loss fine structure of aluminum

Inelastic electron scattering experiments in a transmission electron microscope provide a probe of core electron excitations that have binding energies below 2 keV, and that are localized within submicron diameter sample volumes. Extended electron energy‐loss fine‐structure measurements which show the variation with temperature of the mean squared relative displacement of aluminum yield a localized measurement of the Debye temperature which is in excellent agreement with macroscopic measurements

REVENUE IMPACTS OF MPP BRANDED FUNDS: A FIRM LEVEL ANALYSIS

The USDA recently redirected the Market Access Program (MAP) to allocate all branded products export promotion funds to small firms and cooperatives. The redirection was, in part, a response to reports by the General Accounting Office that were critical of past allocations of export promotion funds to large, experienced exporters. This study uses a firm level analysis to examine firms' effectiveness in using Market Promotion Program (MPP, which is now the MAP) funds to increase revenues. Whereas point estimates suggested that smaller firms were more effective in translating MPP funds into increased revenue than larger firms, these point estimates for small firms were statistically indistinguishable from zero. In contrast, large firms showed an increase in revenue of greater than one dollar for every dollar of MPP funds. Further, the revenue increase was statistically significant. Thus, the firm level analysis supports neither the GAO hypotheses nor the recent program changes.export promotion programs, export sales, export revenues, Market Promotion Program, firm-level analysis, joint estimation, Financial Economics,