Industry reallocations in a globalizing economy

We distill the main insights from recent trade models on firms responses to globalisation. Our primary aim is to assess the economic impact and the welfare implications of the resulting reallocation of resources across firms and countries. In sodoing, we bring theory into life through the numerical implementation of a theoretical framework calibrated on European data, which encompasses aspects of economic geography, firm heterogeneity, and firms organizational choices. Our final purpose isto provide a comprehensive background for empirical investigations and to stimulate further theoretical research.international integration, resource reallocation, economic geography, firm heterogeneity, multinationals

Measuring Cluster Stability for Bayesian Nonparametrics Using the Linear Bootstrap

Clustering procedures typically estimate which data points are clustered together, a quantity of primary importance in many analyses. Often used as a preliminary step for dimensionality reduction or to facilitate interpretation, finding robust and stable clusters is often crucial for appropriate for downstream analysis. In the present work, we consider Bayesian nonparametric (BNP) models, a particularly popular set of Bayesian models for clustering due to their flexibility. Because of its complexity, the Bayesian posterior often cannot be computed exactly, and approximations must be employed. Mean-field variational Bayes forms a posterior approximation by solving an optimization problem and is widely used due to its speed. An exact BNP posterior might vary dramatically when presented with different data. As such, stability and robustness of the clustering should be assessed. A popular mean to assess stability is to apply the bootstrap by resampling the data, and rerun the clustering for each simulated data set. The time cost is thus often very expensive, especially for the sort of exploratory analysis where clustering is typically used. We propose to use a fast and automatic approximation to the full bootstrap called the "linear bootstrap", which can be seen by local data perturbation. In this work, we demonstrate how to apply this idea to a data analysis pipeline, consisting of an MFVB approximation to a BNP clustering posterior of time course gene expression data. We show that using auto-differentiation tools, the necessary calculations can be done automatically, and that the linear bootstrap is a fast but approximate alternative to the bootstrap.Comment: 9 pages, NIPS 2017 Advances in Approximate Bayesian Inference Worksho

Anderson transition and multifractals in the spectrum of the Dirac operator of Quantum Chromodynamics at high temperature

We investigate the Anderson transition found in the spectrum of the Dirac operator of Quantum Chromodynamics (QCD) at high temperature, studying the properties of the critical quark eigenfunctions. Applying multifractal finite-size scaling we determine the critical point and the critical exponent of the transition, finding agreement with previous results, and with available results for the unitary Anderson model. We estimate several multifractal exponents, finding also in this case agreement with a recent determination for the unitary Anderson model. Our results confirm the presence of a true Anderson localization-delocalization transition in the spectrum of the quark Dirac operator at high-temperature, and further support that it belongs to the 3D unitary Anderson model class.Comment: 10 pages, 6 figure

Successfull Blossom Thinning and Crop Load Regulation for Organic Apple Growing with Potassium-bi-carbonate (Armicarb(R)): Results of Field Experiments over 3 Years and with 11 Cultivars

With field trials over 3 years in a commercial organic orchard in Switzerland we have tested the efficacy of Armicarb® (potassium-bi-carbonate) for flower thinning in organic apple production. Over time, Armicarb was tested on 11 cultivars, at different application periods, in different concentrations, and always in comparison to other agents that are already allowed for thinning in organic fruit production in the European Union as e.g. lime sulphur, molasses, mechanical rope-thinner or combinations of methods. Armicarb proved to be an efficient and reliable thinning agent with an efficacy similar to the now recommended methods with rope device, molasses or lime sulphur but has the advantage to be an environmentally very friendly product. On the other hand, the risk for fruit russeting is comparably elevated especially with cultivars ‘Elstar’, ‘Golden Del.’ ’and ‘Gala’. Finally, we have elaborated cultivar-specific recommendations for the use of Armicarb for thinning purposes, which were the basis for the Swiss Federal approval to use Armicarb for thinning in conventional and organic apple production in 2011/2012

Studying the coincidence excess between EXPLORER and NAUTILUS during 1998

The coincidences between EXPLORER and NAUTILUS during 1998 (Astone et al. 2001) are more deeply studied. It is found that the coincidence excess is greater in the ten-day period 7-17 September 1998 and it occurs at the sidereal hour 4, when the detectors axes are perpendicular to the Galactic Disk. The purpose of this paper is to bring our results with the GW detectors to the attention of scientists working in the astrophysical field, and ask them whether are they aware of any special phenomenon occurring when EXPLORER and NAUTILUS showed a coincidence excess.Comment: 5 pages, 7 figures, submitted to A &

Analyticity and crossing symmetry of the eikonal amplitudes in gauge theories

After a brief review and a more refined analysis of some relevant analyticity properties (when going from Minkowskian to Euclidean theory) of the high-energy parton-parton and hadron-hadron scattering amplitudes in gauge theories, described nonperturbatively, in the eikonal approximation, by certain correlation functions of two Wilson lines or two Wilson loops near the light cone, we shall see how these same properties lead to a nice geometrical interpretation of the crossing symmetry between quark-quark and quark-antiquark eikonal amplitudes and also between loop-loop eikonal amplitudes. This relation between Minkowskian-to-Euclidean analyticity properties and crossing symmetry is discussed in detail and explicitly tested in the first orders of perturbation theory. Some nonperturbative examples existing in the literature are also discussed.Comment: Completely revised version with new comments, new references and new figures; 37 pages + 5 figure

High-energy hadron-hadron (dipole-dipole) scattering from lattice QCD

In this paper the problem of high-energy hadron-hadron (dipole-dipole) scattering is approached (for the first time) from the point of view of lattice QCD, by means of Monte Carlo numerical simulations. In the first part, we give a brief review of how high-energy scattering amplitudes can be reconstructed, using a functional-integral approach, in terms of certain correlation functions of two Wilson loops and we also briefly recall some relevant analyticity and crossing-symmetry properties of these loop-loop correlation functions, when going from Euclidean to Minkowskian theory. In the second part, we shall see how these (Euclidean) loop-loop correlation functions can be evaluated in lattice QCD and we shall compare our numerical results with some nonperturbative analytical estimates that appeared in the literature, discussing in particular the question of the analytic continuation from Euclidean to Minkowskian theory and its relation to the still unsolved problem of the asymptotic s-dependence of the hadron-hadron total cross sections.Comment: Revised version (to be published in Phys. Rev. D) with new comments in section 4, a new figure [Fig. 6], two new references in Refs. [3] and [34], and some other minor changes; 27 pages, 17 figure