Competitive Equilibrium in Markets for Votes

We develop a competitive equilibrium theory of a market for votes. Before voting on a binary issue, individuals may buy and sell their votes with each other. We definne ex ante vote-trading equilibrium, identify weak sufficient conditions for existence, and construct one such equilibrium. We show that this equilibrium must always result in dictatorship and the market generates welfare losses, relative to simple majority voting, if the committee is large enough. We test the theoretical implications by implementing a competitive vote market in the laboratory using a continuous open-book multi-unit double auction

Optimization of a 10G recirculating loop test bed

An optical fiber recirculating loop is a device used to experiment and study long haul transmissions for optical fiber communication applications. It simulates long distance communications by making the signal circulate through a loop containing one or multiple spans of optical fiber a certain number of times, saving the expensive cost of the equipment needed to reach thousands of kilometers. This bachelor thesis aims to optimize the 10G optical recirculating loop test bed placed in the Network Laboratory of ETS University. This loop contains approximately 160 km of optical fiber, two dispersion compensator modules (DCM) and four EDFA amplifiers. The signal under test is a 10G (OC-192) NRZ in a DWDM 50 GHz channel span. Test bed is characterized and various configurations are studied to optimize its performance. Different software is developed in order to control the loop and obtain results of the quality of transmission of the signal after it. Finally, different experiments are performed and results are provided to demonstrate the operation.Un loop recirculador de fibra óptica es un dispositivo utilizado para estudiar comunicaciones por fibra óptica a larga distancia. Este dispositivo simula estas transmisiones haciendo circular el señal dentro un loop cerrado que contiene uno o diversos spans de fibra óptica un numero determinado de veces. Con este dispositivo se ahorra el coste del equipamiento necesario para un sistema convencional. Este proyecto pretende optimizar el banco de pruebas 10G recirulating loop situado en el "Network Laboratory" de la universidad ETS de Montreal. Este loop recirculador contiene aproximadamente 160 km de fibra óptica, dos modulos compensadores de la dispersión (DCM) i cuatro amplificadores EDFA. El señal estudiado es un OC-192 con modulación OOK NRZ multiplexado en DWDM con una separación entre canales de 50 GHz. El banco de pruebas es caracterizado y distintas configuraciones son estudiadas para optimizar su rendimiento. Diferentes herramientas de software son programadas para controlar el loop y obtener resultados de la calidad del señal. Finalmente, los resultados de los experimentos son expuestos para demostrar el funcionamiento.Un loop recirculador de fibra òptica és un dispositiu utilitzat per estudiar comunicacions per fibra òptica a llarga distància. Aquest dispositiu simula aquestes comunicacions fent circular el senyal dins un loop tancat que conte un o diversos spans de fibra òptica un cert nombre de vegades. Estalviant el cost en equipament que suposa un sistema convencional. Aquest projecte pretén optimitzar el banc de test 10G recirulating loop situat al "Network Laboratory" de la universitat ETS de Montreal. Aquest loop recirculador conté aproximadament 160 km de fibra òptica, dos mòduls compensadors de la dispersió (DCM) i quatre amplificadors EDFA. El senyal estudiat és OC-192 amb modulació OOK NRZ multiplexat en DWDM amb una separació entre canals de 50 GHz. El banc de proves és caracteritzat i diferents configuracions són estudiades per optimitzar el seu rendiment. Diverses eines de software per controlar el loop i obtenir resultats de la qualitat de transmissió del senyal són desenvolupades durant el projecte. Finalment els resultats de diferents experiments són exposats per demostrar el funcionament

The baryon octet magnetic moments to all orders in flavor breaking; an application to the problem of the strangeness in the nucleon

Using the general QCD parametrization (GP) we display the magnetic moments of the octet baryons including all flavor breaking terms to any order. The hierarchy of the GP parameters allows to estimate a parameter $g_{0}$ related to the quark loops contribution of the proton magnetic moment; its order of magnitude is predicted to be inside a comparatively small interval including the value given recently by Leinweber et al. by a lattice QCD calculationComment: (13 pages- version accepted for publication Phys.Rev.D. Note added in last section, 2 references adde

Disconnected Electromagnetic Form Factors

Preliminary results of a calculation of disconnected nucleon electromagnetic factors factors on the lattice are presented. The implementation of the numerical subtraction scheme is outlined. A comparison of results for electric and magnetic disconnected form factors on two lattice sizes with those of the Kentucky group is presented. Unlike previous results, the results found in this calculation are consistent with zero in these sectors.Comment: Lattice 2000 (Hadronic Matrix Elements), 4 pages, 6 fig

The Power of Sunspots: An Experimental Analysis

We present an experiment in which extrinsic information (signals) may generate sunspot equilibria. The underlying coordination game has a unique symmetric non-sunspot equilibrium, which is also risk-dominant. Other equilibria can be ordered according to risk dominance. We compare treatments with different salient, but extrinsic signals. By increasing the precision of private signals, we manipulate the available public information, which allows us to measure the force of extrinsic signals. We also vary the number of signals and combine public and private signals, allowing us to see how subjects aggregate available (and possibly irrelevant) information. Results indicate that sunspot equilibria emerge naturally if there are salient (but extrinsic) public signals. However, salient private signals of high precision may also cause sunspot-driven behavior, even though this is no equilibrium. The higher the precision of signals and the easier they can be aggregated, the more powerful they are in dragging behavior away from the risk-dominant to risk-dominated strategies. Sunspot-driven behavior may lead to welfare losses and exert negative externalities on agents, who do not receive extrinsic signals.coordination games, strategic uncertainty, sunspot equilibria, irrelevant information

The Nucleon Anapole Form Factor in Chiral Perturbation Theory to Sub-leading Order

The anapole form factor of the nucleon is calculated in chiral perturbation theory to sub-leading order. This is the lowest order in which the isovector anapole form factor does not vanish. The anapole moment depends on counterterms that reflect short-range dynamics, but the momentum dependence or the form factor is determined by pion loops in terms of parameters that could in principle be fixed from other processes. If these parameters are assumed to have natural size, the sub-leading corrections do not exceed ~ 30% at momentum Q ~ 300 MeV.Comment: 11 pages, 6 figures, epsf.sty, submitted to Phys. Lett

Flavor content of nucleon form factors in the space- and time-like region

I discuss a two-component model of nucleon form factors in which the external photon couples both to an intrinsic three-quark structure and to a meson cloud via vector-meson dominance, and present a simultaneous analysis of the electromagnetic form factors of the nucleon in the space- and time-like regions as well as their strangeness content.Comment: 7 pages, 3 figures, invited talk at FB18, Santos, Brazil, August 21-26, 200