Ambiguity Aversion, the Equity Premium and the Welfare Costs of Business Cycles

We examine the potential importance of consumer ambiguity aversion for asset prices and how consumption ‡fluctuations influence consumer welfare. First, considering a simple Mehra-Prescott-style endowment economy with a representative agent facing consumption fluctuations calibrated to match U.S. data, we study to what extent ambiguity aversion can deliver asset prices that are consistent with data: a high return on equity and a low return on riskfree bonds. For some configurations of preference parameters— a discount factor, a degree of relative risk aversion, and a measure of ambiguity aversion— we find that it can. Then, we use these parameter configurations to investigate how much consumers would be willing to pay to reduce endowment fluctuations to zero, thus delivering a Lucas-style welfare cost of fluctuations. These costs turn out to be very large: consumers are willing to pay over 10% of consumption in permanent terms.Ambiguity aversion; asset prices; business cycle

Determinants of Capital Intensive and R&D Intensive Foreign Direct Investment

We study the determinants of capital intensity and technology content of foreign direct investment, an important economic driving force for developing countries. For this purpose, we use sectoral industry data on U.S. foreign investment abroad, and data on host countries' institutional characteristics, like investment climate, protection of property rights, labor standards and constitutional arrangements. Our regressions show that better protection of property rights has a significant positive effect on R&D but not on capital intensive capital flows. There is evidence that an increase in workers' bargaining power results in a reduction of capital and technologically intensive foreign investment. And although the evidence with respect to constitutional arrangements is not very strong, presidential regimes appear to be less able than parliamentary ones to deliver policies attracting R&D intensive capital flows. This is consistent with recent research on the effects of constitutional arrangements on economic growth.FDI

Government Policy in the Formal and Informal Sectors

The paper quantitatively investigates, in general equilibrium, the interaction between the firms' choice to operate in the formal or the informal sector and government policy on taxation and enforcement, given a level of regulation. A static version of Ghironi and Melitz’s (2005) industry model is used to show that firms with lower productivity endogenously choose to operate in the informal sector. I use cross-country data on taxes, measures of informality, and measures of regulation (entry and compliance costs, red tape, etc) to back out how high the enforcement levels must be country by country to make the theory match the data. Welfare gains from policy reforms can be fairly large. I find also that welfare gains from reducing regulation are almost twice those computed for the policy reform. Finally, distortions associated with informality account for a factor of 1.5 of the output per capita difference between the richest and the poorest countries.Informal economy; General equilibrium; Regulation

Fluorescence and Hybrid Detection Aperture of the Pierre Auger Observatory

The aperture of the Fluorescence Detector (FD) of the Pierre Auger Observatory is evaluated from simulated events using different detector configurations: mono, stereo, 3-FD and 4-FD. The trigger efficiency has been modeled using shower profiles with ground impacts in the field of view of a single telescope and studying the trigger response (at the different levels) by that telescope and by its neighbours. In addition, analysis cuts imposed by event reconstruction have been applied. The hybrid aperture is then derived for the Auger final extension. Taking into account the actual Surface Detector (SD) array configuration and its trigger response, the aperture is also calculated for a typical configuration of the present phase.Comment: contribution to the 29th International Cosmic Ray Conference, Pune, India, 3-10 August 200

O DISCURSO DO SÉCULO E A CRÍTICA DE ROUSSEAU

Originalmente publicado em: Almanaque: Cadernos de Literatura e Ensaio, São Paulo: Brasiliense, n. 1, p. 9-12, 1976.A publicação deste texto nos Cadernos de Ética e Filosofia Política é uma homenagem ao professor Bento Prado Jr. (1937-2007), que integrava o Conselho Editorial da revista. Os editores dos Cadernos agradecem a Raquel de Almeida Prado por permitir a reprodução integral do texto

The Offline Software Framework of the Pierre Auger Observatory

The Pierre Auger Observatory is designed to unveil the nature and the origins of the highest energy cosmic rays. The large and geographically dispersed collaboration of physicists and the wide-ranging collection of simulation and reconstruction tasks pose some special challenges for the offline analysis software. We have designed and implemented a general purpose framework which allows collaborators to contribute algorithms and sequencing instructions to build up the variety of applications they require. The framework includes machinery to manage these user codes, to organize the abundance of user-contributed configuration files, to facilitate multi-format file handling, and to provide access to event and time-dependent detector information which can reside in various data sources. A number of utilities are also provided, including a novel geometry package which allows manipulation of abstract geometrical objects independent of coordinate system choice. The framework is implemented in C++, and takes advantage of object oriented design and common open source tools, while keeping the user side simple enough for C++ novices to learn in a reasonable time. The distribution system incorporates unit and acceptance testing in order to support rapid development of both the core framework and contributed user code.Comment: 4 pages, 2 figures, presented at IEEE NSS/MIC, 23-29 October 2005, Puerto Ric

“Ars”: Visual Arts magazine by PPGAV, ECA/University of Sao Paulo

The “Ars” magazine, created by the graduate program in Visual Arts from Escola de Comunicação e Artes [School of Arts and Communication], at the University of Sao Paulo, gathers art relevant works by students at the university and outside of the academia. The magazine suggests that the issues involving an art school should not remain restricted to the academic environment, but should be taken as a cultural debate beyond the University walls and doubt art perspectives in a contemporary context