General equilibrium with asymmetric information: a dual approach

We study markets where the characteristics or decisions of certain agents are relevant but not known to their trading partners. Assuming exclusive transactions, the environment is described as a continuum economy with indivisible commodities. We characterize incentive efficient allocations as solutions to linear programming problems and appeal to duality theory to demonstrate the generic existence of external effects in these markets. Because under certain conditions such effects may generate non-convexities, randomization emerges as a theoretic possibility. In characterizing market equilibria we show that, consistently with the personalized nature of transactions, prices are generally non-linear in the underlying consumption. On the other hand, external effects may have critical implications for market efficiency. With adverse selection, in fact, cross-subsidization across agents with different private information may be necessary for optimality, and so, the market need not even achieve an incentive efficient allocation. In contrast, for the case of a single commodity, we find that when informational asymmetries arise after the trading period (e.g. moral hazard; ex post hidden types) external effects are fully internalized at a market equilibrium.

A dual characterization of incentive efficiency

We show that incentive efficient allocations in economies with adverse selection and moral hazard can be determined as optimal solutions to a linear programming problem and we use duality theory to obtain a complete characterization of the optima. Our dual analysis identifies welfare effects associated with the incentives of the agents to truthfully reveal their private information. Because these welfare effects may generate non-convexities, incentive efficient allocations may involve randomization. Other properties of incentive efficient allocations are also derived.

Diseño e implementación de un divisor de potencia en banda dual con estructuras metamateriales basadas en CSRRs

L'electromagnetisme és una branca de la física que està en continu estudi. Fins a mitjans de la dècada dels 60 es pensava que, per a la propagació de les ones electromagnètiques fos possible, els medis propagatius havien de presentar una permitivitat dielèctrica i una permeabilitat magnètica simultàniament positives. No obstant, Victor G. Veselago va revolucionar la teoria electromagnètica amb la idea dels medis amb ε i μ negatives i va donar amb això origen als medis metamaterials. En el present treball s'estudiaran els principis físics en els que es fonamenten els metamaterials. Es veuran algunes de les seves característiques que els converteixen en medis exòtics i com aquestes poden ser utilitzades en el desenvolupament de dispositius amb prestacions difícils d'obtenir amb les tecnologies convencionals. A continuació s'aplicaran els conceptes tractats en el disseny d'un inversor d'impedàncies implementat mitjançant ressonadors en anells oberts complementaris. Aquest dispositiu, que presentarà un funcionament en banda dual, serà utilitzat en el posterior disseny d'un divisor de potencia. Finalment es realitzarà la implementació física del divisor de potencia dissenyat i es verificarà el seu correcte funcionament amb les mesures pertinents.

Desfassador banda dual basat en híbrid multibanda per aplicacions wireless

El primer objectiu del projecte és l’estudi i disseny d’un desfassador bi – banda reconfigurable per integrar en sistemes d’antenes intel·ligents i amb aplicació a sistemes dual band WLAN operant en els marges freqüencials 2.4 - 2.5 GHz i 5.15 – 5.35GHz. El desfassador que es proposa realitzar està basat en un acoblador híbrid multibanda, diplexors i circuits reconfigurables commutats amb díodes PIN. El segon objectiu del projecte és l’aprenentatge de la metodologia de disseny de circuits d’RF i més concretament les següents etapes: estudi i disseny teòric (analític), simulació circuital (ADS), simulació electromagnètica (Momentum), cosimulació circuital-electromagnètica i fabricació, així com les diferents interacions i mecanismes d’optimització entre aquestes etapes.

Privatization and competition in the delivery of local services: An empirical examination of the dual market hypothesis

This paper empirically analyses the hypothesis of the existence of a dual market for contracts in local services. Large firms that operate on a national basis control the contracts for delivery in the most populated and/or urban municipalities, whereas small firms that operate at a local level have the contracts in the least populated and/or rural municipalities. The dual market implies the high concentration and dominance of major firms in large municipalities, and local monopolies in the smaller ones. This market structure is harmful to competition for the market as the effective number of competitors is low across all municipalities. Thus, it damages the likelihood of obtaining cost savings from privatization.

A theoretical and practical study on linear reforms of dual taxes

We extend the linear reforms introduced by Pf¨ahler (1984) to the case of dual taxes. We study the relative effect that linear dual tax cuts have on the inequality of income distribution -a symmetrical study can be made for dual linear tax hikes-. We also introduce measures of the degree of progressivity for dual taxes and show that they can be connected to the Lorenz dominance criterion. Additionally, we study the tax liability elasticity of each of the reforms proposed. Finally, by means of a microsimulation model and a considerably large data set of taxpayers drawn from 2004 Spanish Income Tax Return population, 1) we compare different yield-equivalent tax cuts applied to the Spanish dual income tax and 2) we investigate how much income redistribution the dual tax reform (Act ‘35/2006’) introduced with respect to the previous tax.

L’Evolució del vot dual a Catalunya

El principal valor afegit d’aquest treball rau en la troballa de que la valoració dels candidats a la presidència de la Generalitat és la variable que té més importància a l’hora d’explicar la propensió d’un català a emetre un vot dual. Així per exemple, i pel cas del vot dual PSC-CiU a finals dels vuitanta i principis dels noranta, els catalans que es decantaven per l’opció socialista a les eleccions generals i per la federació nacionalista als comicis autonòmics eren aquells que valoraven millor (pitjor) Jordi Pujol (Raimon Obiols). I a conclusions similars s’arriba si s’analitza aquesta mateixa modalitat de vot dual en altres punts del temps, o altres modalitats de vot dual. El treball s’estructura de la manera següent. En primer lloc, es defineix l’objecte d’estudi i les seves distintes modalitats. A continuació, s’ofereixen unes primeres dades de tipus descriptiu sobre el fenomen del vot dual a Catalunya. En els apartats següents, s’emmarquen teòricament les hipòtesis la validesa de les quals es busca comprovar a través dels models economètrics. La secció dedicada al disseny de la investigació serveix de preàmbul a l’anàlisi quantitativa de les causes del vot dual a Catalunya. Per últim, un breu apartat de conclusions recull les principals aportacions del treball, i aventura possibles línees d’investigació futures.

The learning process as a cooperative task among teachers and students

This research project gathers several ideas and guidelines on professional improvement as a teacher. This study includes two empirical studies. The first one focuses mainly on the teacher's figure. It is meant to be a study of the several resources that the teacher uses in order to construct the student's knowledge in an English classroom context. The second empirical study focuses on the students. It is a study on how students learn cooperatively by analyzing their oral productions when working in small groups

Teachers' reactions on students' responses: essential for an adequate task monitoring

This research project analyzes the reactions the teacher has on students' responses. Different techniques as discourse markers, types of questions and repair sequences are taken into account, but the author puts a special emphasis on non-verbal communication. To be aware of all these ways of reacting in a class interaction is essential for an adequate task monitoring

New pre-dual space of Morrey space

In this paper we give new characterization of the classical Morrey space. Complementary global Morrey-type spaces are introduced. It is proved that for particular values of parameters these spaces give new pre-dual space of the classical Morrey space. We also show that our new pre-dual space of the Morrey space coincides with known pre-dual spaces.

Estudio y diseño de filtros pasobanda y en banda dual basados en resonadores microstrip open-loop acoplados

El proyecto está dedicado al estudio y diseño de filtros paso-banda y en banda dual con tecnología microstrip mediante estructuras resonantes de tipo open-loop. Se ha llevado a cabo el diseño de un filtro paso-banda con respuesta Chebyshev, un filtro pasobanda con ceros de transmisión y un filtro de banda dual para WCDMA y WiFi, empleado el método de diseño para filtros basados en resonadores inter-acoplados. Se presentan los modelos eléctricos de los filtros de RF simulados junto con sus respectivos layouts y se comparan las respuestas obtenidas de los dispositivos con las respuestas ideales. En el proyecto se realiza un estudio del comportamiento de los diferentes tipos de acoplamiento entre resonadores open-loop en función de la geometría de la estructura. Las tendencias de comportamiento de los acoplamientos permiten el diseño y colocación de los resonadores para satisfacer las especificaciones del filtro.

Intelligent task-level grasp mapping for robot control

In the future, robots will enter our everyday lives to help us with various tasks.For a complete integration and cooperation with humans, these robots needto be able to acquire new skills. Sensor capabilities for navigation in real humanenvironments and intelligent interaction with humans are some of the keychallenges.Learning by demonstration systems focus on the problem of human robotinteraction, and let the human teach the robot by demonstrating the task usinghis own hands. In this thesis, we present a solution to a subproblem within thelearning by demonstration field, namely human-robot grasp mapping. Robotgrasping of objects in a home or office environment is challenging problem.Programming by demonstration systems, can give important skills for aidingthe robot in the grasping task.The thesis presents two techniques for human-robot grasp mapping, directrobot imitation from human demonstrator and intelligent grasp imitation. Inintelligent grasp mapping, the robot takes the size and shape of the object intoconsideration, while for direct mapping, only the pose of the human hand isavailable.These are evaluated in a simulated environment on several robot platforms.The results show that knowing the object shape and size for a grasping taskimproves the robot precision and performance

Using qualia information to identify lexical semantic classes in an unsupervised clustering task

Acquiring lexical information is a complex problem, typically approached by relying on a number of contexts to contribute information for classification. One of the first issues to address in this domain is the determination of such contexts. The work presented here proposes the use of automatically obtained FORMAL role descriptors as features used to draw nouns from the same lexical semantic class together in an unsupervised clustering task. We have dealt with three lexical semantic classes (HUMAN, LOCATION and EVENT) in English. The results obtained show that it is possible to discriminate between elements from different lexical semantic classes using only FORMAL role information, hence validating our initial hypothesis. Also, iterating our method accurately accounts for fine-grained distinctions within lexical classes, namely distinctions involving ambiguous expressions. Moreover, a filtering and bootstrapping strategy employed in extracting FORMAL role descriptors proved to minimize effects of sparse data and noise in our task.

Productivity Growth during the English Industrial Revolution: A Dual Approach

This paper presents new estimates of total factor productivity growth in Britain for the period 1770-1860. We use a dual technique recently popularized by Hsieh (1999), and argue that the estimates we derive from factor prices are of similar quality to quantity-based calculations. Our results provide further evidence, derived from this independent set of sources, that productivity growth during the British Industrial Revolution was relatively slow. During the years 1770-1800, TFP growth was close to zero, according to our estimates. The period 1800-1830 experienced an acceleration of productivity growth. The Crafts-Harley view of the Industrial Revolution is thus reinforced. We also consider alternative explanations of slow productivity growth, and reject the interpretation that focuses on the introduction of steam as a general purpose technology.

Cognitive stimulation through task-oriented telerobotics

The project presented, iCognos, consists of a flexible platform to assist end-users in performing a series of mental tasks with a sensitized mobile telerobotic platform aimed at mitigating the problems associated to cognitive disorders with an ecological cognition approach.