Protection for Sale Under Monopolistic Competition: An Empirical Investigation

This paper proposes a general empirical framework to estimate the protection-for-sale model, where the protection regime shifts according to a sector's market structure (perfectly or monop-olistically competitive). We base the protection structure on Grossman and Helpman (1994) for the subset of perfectly competitive sectors and on Chang (2005) for the subset of monop- olistically competitive sectors. The two protection regimes are simultaneously estimated with joint constraints. The results of the J-test consistently reject the homogeneous (perfect compe- tition) protection-for-sale model often adopted in previous literature and suggest a direction of improvement toward the proposed heterogeneous protection structure model.endogenous trade policy; campaign contribution; monopolistic competition; intrain- dustry trade; import penetration

The WTO Trade Effect

This paper reexamines the GATT/WTO membership effect on bilateral trade flows, using nonparametric methods including pair-matching, permutation tests, and a Rosenbaum (2002) sensitivity analysis. Together, these methods provide an estimation framework that is robust to misspecification biases, allows general forms of heterogeneous treatment effects, and addresses potential hidden selection biases. This is in contrast to most conventional parametric studies on this issue. Our results suggest large GATT/WTO trade-promoting e®ects, robust to various restricted matching criteria, alternative indicators for GATT/WTO involvement, different matching methodologies, non-random incidence of positive trade flows, and inclusion of multilateral resistance terms.Trade flow,Treatment effect,Matching,Permutation test,Signed-rank test,Sensitivity analysis

Protection for Sale Under Monopolistic Competition : An Empirical Investigation

This paper proposes a general empirical framework to estimate the protection-for-sale model, where the protection regime shifts according to a sector's market structure (perfectly or monopolistically competitive). We base the protection structure on Grossman and Helpman (1994) for the subset of perfectly competitive sectors and on Chang (2005) for the subset of monopolistically competitive sectors. The two protection regimes are simultaneously estimated with joint constraints. The results of the J-test consistently reject the homogeneous (perfect competition) protection-for-sale model often adopted in previous literature and suggest a direction of improvement toward the proposed heterogeneous protection structure model.endogenous trade policy, campaign contribution, monopolistic competition, intraindustry trade, import penetration

The WTO Trade Effect

Rose (2004) showed that the WTO or its predecessor, the GATT, did not promote trade, based on conventional econometric analysis of gravity-type equations of trade. We argue that conclusions regarding the GATT/WTO trade effect based on gravity-type equations are arbitrary and subject to parametric misspecifications. We propose using nonparametric matching methods to estimate the `treatment effect' of GATT/WTO membership, and permutation-based inferential procedures for assessing statistical significance of the estimated effects. A sensitivity analysis following Rosenbaum (2002) is then used to evaluate the sensitivity of our estimation results to potential selection biases. Contrary to Rose (2004), we find the effect of GATT/WTO membership economically and statistically significant, and far greater than that of the Generalized System of Preferences (GSP).GATT/WTO, GSP, treatment effect, matching, permutation test, signed-rank test, sensitivity analysis

Rotationally Resolved Laser Spectroscopy of the 3s2Σ+ ← 2p2II Transition in 6Li20Ne and 7Li20Ne Van Der Waals Molecules

The rotationally resolved absorption spectrum of the 6Li20Ne and 7Li20Ne 3s2Σ+ ← 2p2 II transition has been observed. For each isotope, thirteen vibrational transitions from four vibrational levels (v =0, 1, 2, and 3) of the lower 2p2 II to six (v’=0, 1, 2, 3, 4, and 5) of the upper 3s*Σ+ electronic state have been rotationally analyzed. Adiabatic potentials and dissociation energies for both states have been obtained through an inverse perturbation analysis. For the 2p2II state, a well depth of 212(5) cm-1 and an equilibrium separation of 4.36(2) a,, have been obtained. Analysis of the 3s2Σ+ electronic state has revealed a barrier greater than 60 cm\u27-1 above the atomic Li 3s asymptote and a well of 570(7) cm-1 located at 4.11(1) ao below the asymptote. An anomalously large spin-orbit constant of A =2.77(3) cm\u271 was determined for the 2p2II (v =0) state while no splitting is observed for transitions out of any 2p2II level with v \u3e0

The Octonions

The octonions are the largest of the four normed division algebras. While somewhat neglected due to their nonassociativity, they stand at the crossroads of many interesting fields of mathematics. Here we describe them and their relation to Clifford algebras and spinors, Bott periodicity, projective and Lorentzian geometry, Jordan algebras, and the exceptional Lie groups. We also touch upon their applications in quantum logic, special relativity and supersymmetry.Comment: 56 pages LaTeX, 11 Postscript Figures, some small correction

Entangling Higgs production associated with a single top and a top-quark pair in the presence of anomalous top-Yukawa coupling

The ATLAS and CMS collaborations observed a mild excess in the associated Higgs production with a top-quark pair ($t\bar t h$) and reported the signal strengths of $\mu_{tth}^{\rm ATLAS}=1.81\pm 0.80$ and $\mu_{tth}^{\rm CMS}=2.75\pm 0.99$ based on the data collected at $\sqrt{s}$= 7 and 8 TeV. Although, at the current stage, there is no obvious indication whether the excess is real or due to statistical fluctuations, here we perform a case study of this mild excess by exploiting the strong entanglement between the associated Higgs production with a single top quark ($thX$) and $t\bar t h$ production in the presence of anomalous top-Yukawa coupling. As well known, $t\bar t h$ production only depends on the absolute value of the top-Yukawa coupling. Meanwhile, in $thX$ production, this degeneracy is lifted through the strong interference between the two main contributions which are proportional to the top-Yukawa and the gauge-Higgs couplings, respectively. Especially, when the relative sign of the top-Yukawa coupling with respect to the gauge-Higgs coupling is reversed, the $thX$ cross section can be enhanced by more than one order of magnitude. We perform a detailed study of the influence of $thX$ production on $t\bar{t}h$ production in the presence of the anomalous top-Yukawa coupling and point out that it is crucial to include $thX$ production in the analysis of the $t\bar t h$ data to pin down the sign and the size of the top-Yukawa coupling in future. While assuming the Standard Model (SM) value for the gauge-Higgs coupling, we vary the top-Yukawa coupling within the range allowed by the current LHC Higgs data. We consider the Higgs decay modes into multileptons, $b\bar b$ and $\gamma\gamma$ putting a particular emphasis on the same sign dilepton events. We also discuss ...Comment: 32 pages, 10 figures, 12 tables, to appear in JHE