A Discussion on Armington Trade Substitution Elasticities

Applied partial and general equilibrium models used to examine trade policy are almost universally sensitive to trade elasticities. Indeed, the Armington elasticity, the degree of substitution between domestic and imported goods, is a key behavioral parameter that drives the quantitative, and sometimes the qualitative, results that policymakers use. While standard transparent approaches to econometric estimation of these elasticities have been offered for the last 30 years, the estimates are viewed as too small by many trade economists. A few robust findings emerge from the econometric literature: (1) more disaggregate analyses find higher elasticities, (2) long-run estimates are higher than short-run estimates, and (3) time series analyses generally find lower elasticities relative to cross-sectional studies. We offer simulation results to illustrate the sensitivity of general equilibrium models to Armington elasticites. We conclude with remarks on the current challenges that remain in determining these important parameters.International Relations/Trade,

A Discussion on Armington Trade Substitution Elasticities

Applied partial and general equilibrium models used to examine trade policy are almost universally sensitive to trade elasticities. Indeed, the Armington elasticity, the degree of substitution between domestic and imported goods, is a key behavioral parameter that drives the quantitative, and sometimes the qualitative, results that policymakers use. While standard transparent approaches to econometric estimation of these elasticities have been offered for the last 30 years, the estimates are viewed as too small by many trade economists. A few robust findings emerge from the econometric literature: (1) more disaggregate analyses find higher elasticities, (2) long-run estimates are higher than short-run estimates, and (3) time series analyses generally find lower elasticities relative to cross-sectional studies. We offer simulation results to illustrate the sensitivity of general equilibrium models to Armington elasticites. We conclude with remarks on the current challenges that remain in determining these important parameters.Computable general equilibrium; International Trade; Armington; elasticity

An Estimation of U.S. Industry-Level Capital-Labor Substitution

A key parameter that determines the distributional impacts of a policy shift in general equilibrium models is the elasticity of substitution between capital and labor. Despite the importance of this parameter in applied modeling, its identification continues to pose a challenge. Given the structure of most growth models, we posit that the true relationship between capital and labor is likely to be close to Cobb- Douglas. Using a rich new data set from the Bureau of Economic Analysis, we estimate substitution elasticities for 28 industries, which cover the entire economy, and provide an indication of the long- and short-run estimates. We fail to reject the Cobb-Douglas specification in 20 of the 28 industries. These findings lend support to the Cobb-Douglas specification as a transparent starting point in simulation analysis.Econometric Methods; Time Series Models; Computable General Equilibrium Models

Spectral mode-beat phenomena in a cylindrical microcavity

Detailed spectral analysis of photon scanning tunneling microscope images has been carried out. The analysis of spectral mode-beat phenomena leads to an accurate determination of mode profiles and gives evidence of counterpropagating mode

Citizens and scientists work together to monitor marine alien macrophytes

The introduction of non-indigenous species (NIS) is an ongoing phenomenon which has been pointed out as a major threat to biodiversity at different levels. NIS may in time become invasive (Invasive Alien Species “IAS”) and may cause biodiversity loss and ecosystem service changes. The Mediterranean Sea is an important hotspot for marine NIS (ca. 1,000 such species recorded to date. To reduce the risk of future IAS introduction and to better understand their invasive potential and spread dynamics, monitoring and surveillance plans are required. The creation of permanent alarm systems and public awareness campaigns are crucial for reducing the risk of IAS introduction. Since intensive monitoring programs could be very expensive, citizen science, involving citizens (e.g. tourists, fishermen, divers) in the collection of data, could be a useful tool for providing data on IAS, that would otherwise be impossible to collect because of limitations on time and resources. Citizen science is having an increasing success worldwide. Citizen science projects has rapidly and enormously increased in recent years, also thanks to the wide availability of mobile technologies and internet access that enable an easy and cheap way to communicate, share and interchange data. The value of citizen science has been widely recognized. Of course, in order to be used for scientific purposes and management decisions, the collected data need appropriate quality assurance measures such as validation and verification by taxonomic experts. We report on the experience of two citizen science projects: the Project “Caulerpa cylindracea – Egadi Islands” and the Project “Invasive Algae”, included within the “Seawatchers” platform

High-resolution photon-scanning tunneling microscope measurements of the whispering gallery modes in a cylindrical microresonator

A detailed analysis of spatio-spectral photon scanning tunneling microscope scans of the light intensity inside a cylindrical microresonator has been carried out. By comparing the experimental results with theory, it is shown that the inclusion of spectral mode-beat phenomena is crucial for an accurate analysis of the modes present in the microresonator

Detailed analysis of the intracavity phenomena inside a cylindrical microresonator

Based o­n a rigorous analysis of the intensity distribution inside a cylindrical microresonator (MR), a detailed description of the wavelength and spatial dependence of the intracavity intensity is given. The theory is in accordance with photon scanning tunneling microscopy (PSTM) of an integrated optics MR. Good agreement between the theory and the PSTM measurements is found

Pulse tracking in complex photonic structures

Time-resolved near-field microscopy allows the propagation of ultrafast pulses to be visualized en route while they travel through complex photonic structures. These measurements enable the unambiguous determination of both local phase and group velocities. We illustrate this powerful technique by tracking an ultrashort wavepacket as it completes several round trips in a ring resonator

Design and Fabrication of Terahertz Metallic Gratings on a Two-Wire Waveguide

In this study, we present the design, fabrication and experimental characterization of waveguide-integrated gratings operating at THz frequencie