Prospect theory, diversificação ingênua e propensão a risco de especialistas em mercado: evidência empírica no Brasil

The Prospect Theory is one of the basis of Behavioral Finance and models the investor behavior in a different way than von Neumann and Morgenstern Utility Theory. Behavioral characteristics are evaluated for different control groups, validating the violation of Utility Theory Axioms. Naïve Diversification is also verified, utilizing the 1/n heuristic strategy for investment funds allocations. This strategy causes different fixed and equity allocations, compared to the desirable exposure, given the exposure of the subsample that answered a non constrained allocation question. When compared to non specialists, specialists in finance are less risk averse and allocate more of their wealth on equity.

Bayesian analysis of extreme events with threshold estimation

The aim of this paper is to analyze extremal events using Generalized Pareto Distributions (GPD), considering explicitly the uncertainty about the threshold. Current practice empirically determines this quantity and proceeds by estimating the GPD parameters based on data beyond it, discarding all the information available be10w the threshold. We introduce a mixture model that combines a parametric form for the center and a GPD for the tail of the distributions and uses all observations for inference about the unknown parameters from both distributions, the threshold inc1uded. Prior distribution for the parameters are indirectly obtained through experts quantiles elicitation. Posterior inference is available through Markov Chain Monte Carlo (MCMC) methods. Simulations are carried out in order to analyze the performance of our proposed mode1 under a wide range of scenarios. Those scenarios approximate realistic situations found in the literature. We also apply the proposed model to a real dataset, Nasdaq 100, an index of the financiai market that presents many extreme events. Important issues such as predictive analysis and model selection are considered along with possible modeling extensions.

We're Chained: an analysis of systemic risk in finance

This dissertation presents two papers on how to deal with simple systemic risk measures to assess portfolio risk characteristics. The first paper deals with the Granger-causation of systemic risk indicators based in correlation matrices in stock returns. Special focus is devoted to the Eigenvalue Entropy as some previous literature indicated strong re- sults, but not considering different macroeconomic scenarios; the Index Cohesion Force and the Absorption Ratio are also considered. Considering the S&P500, there is not ev- idence of Granger-causation from Eigenvalue Entropies and the Index Cohesion Force. The Absorption Ratio Granger-caused both the S&P500 and the VIX index, being the only simple measure that passed this test. The second paper develops this measure to capture the regimes underlying the American stock market. New indicators are built using filtering and random matrix theory. The returns of the S&P500 is modelled as a mixture of normal distributions. The activation of each normal distribution is governed by a Markov chain with the transition probabilities being a function of the indicators. The model shows that using a Herfindahl-Hirschman Index of the normalized eigenval- ues exhibits best fit to the returns from 1998-2013.

How to neutralize the adverse developmental effects of the Dutch disease?

This paper addresses the subject of the adverse developmental effects of the Dutch disease: the theory, the experience of Latin America over the last decade, and the economic policy management issues on what to do about it.

Trânsito de saberes e campo representacional na visão dos profissionais da saúde da família e do programa de educação pelo trabalho e para a saúde

The Family Health Strategy (ESF) is emerging as a possible restructuring of services and new practices of intervention in health care; it requires skilled professionals to work with that framework. Within this purpose, we established the Education Programme for Work and Health (PET-Saúde), in order to integrate teaching and service activities, focusing on primary care. On this basis, the aim of this work is to apprehend the social representation of nurse, doctor and dentist (Project PET-Natal Health RN preceptors) on the ESF, while practice field of them. It is a descriptive and exploratory study, with a qualitative approach, carried out in 07 Family Health Units (USF) included in the PET-Saúde Natal (RN). The population was composed of 35 professional components of the primary care team with bachelor's degree of the USF linked to this project. The sample was composed of 05 nurses, 05 physicians and 05 dentists, for a total of 15 subjects. Data were collected through three instruments: the drawing-themed story, a semi-structured individual interviews and field diary. The data relating to the identification of the subjects were entered and tabulated by the Microsoft Excel software 2007 version. The drawing analysis and interpretation is given by the significance attributed to the resource chart from title and keywords assigned by the subjects, considering the ESF as an inductive term. The stories and interviews were transcribed and typed and then subjected to read/listen the material and a lexical analysis through Alceste. After this process, the discursive material was analyzed and discussed by theoretical and methodological feature of the Social Representations theory. The majority of health professionals were female, aged between 46 and 52 years old, married, income less than six minimum wage, time since graduation ranged from 22 to 29 years and working time in the ESF range from 02 to 11 years. From the classification system ALCESTE were selected categories identified by: Category 1 - ESF: relations and territory; Category 2 - Training and bond profile; Category 3 - Working process in the ESF; Category 4 - Articulation between teaching and service; Category 5 - Health care and disease prevention. The representational field construction, while a process, followed the logic of structural cores in existing categories. In this sense, it is clear that the ESF is an environment rich in diversity, experience and relationships with potential such as the relationship "very subject-subject" and the link established between professional-community, but also has some weaknesses such as poor working conditions, lack of popular participation and management support, thus difficulties in the achievement of teamwork. Being essential to that end, the teaching-service aimed at the formation of a new health professional able to work in the ESF. In this research, the training of the representational field encountered a diversity of structural cores, or thoughts on training, about the ESF because of the greater emphasis on the here and now of the interaction between health professionals, the ESF, the community, PET Health-UFRN and students, emphasizing that such proposals are still considered as concepts in the context of recent health and that, therefore, are not fully realized in the social imaginary

Nexus: da relacionalidade do princípio à metafísica do inominável em Nicolau de Cusa

We indicate the idea of nexus or conexio, thought of as intelligible connection with the intelligent, the foundation on which the reason why you can understand and name, even if inadequately, what the intellect sees incomprehensible and unnameably. Thus, it opens a way for our research: we will take the idea of nexus as fundamental to the interpretation of the divine names and the "metaphysics of the unnameably" and we show how the divine names, mainly in possest, mirrored in the Trinity, relatedness of the principle and therefore also the nexus. For that you need to think some preliminary questions: we will place Nicholas of Cusa in the tradition of medieval Christian Neoplatonism, we resume some discussions on the problem of naming and the philosophy of language in his thinking, we will reflect such thinking is molded from active dialogue with the tradition and how it is your speculation is founded upon the dynamic and dialectical relationship between philosophy and theology to be thought of in our text using the relationship between faith and understandig (intellectus). After introductory clarify these issues we will come to consider introductory understanding of the Trinitarian Beginning and speculation about the nexus taking as its starting point from where the De venatione sapientiae nexus or conexio is designed as a hunting field of wisdom and the First Book of De docta ignorantia where the maximum is now thought of as one and triune. From the Second Book of the same work and the Idiota. De mente we will show in what sense the universe and men, as imago dei, imitate the eternal Trinity. Finally, we will resume the notion of the scientia aenigmatica of De beryllo and some information that will clarify that Nicholas assumes the divine names as enigmas. Finally, we will try to show that the enigmatic or symbolic names also mirror the triune Beginning principle. So, before we return some traces of this aspect in some divine names and texts of the "late period" and then conclude with that which in itself already indicates the nexus and therefore the trinity: possest

A theoretical analysis on the intramolecular proton transfer of alpha-alanine in an aqueous medium

Intramolecular proton transfer from oxygen to nitrogen atoms in the alpha-alanine amino acid has been studied by ab initio methods at the HF/6-31G*, HF/6-31 ++ G** and MP2/6-31 ++ G** levels of calculation including the solvent effects by means of self-consistent reaction field theory. An analysis of the results based on the natural bond orbital charges shows that the transition structure presents an imbalance in the sense that the charge shift lags behind the proton transfer and that the bond formation is always in advance with respect to the bond cleavage. All calculation levels show that the barrier height associated with the conformational change on alpha-alanine is larger than the proton transfer process. (C) 1998 Elsevier B.V. B.V. All rights reserved.

Density functional study of the 5-methylcytosine tautomers

B3LYP/6-31++G** calculations to study seven tautomers of 5-methylcytosine in aqueous media have been carried out. Optimized geometries and relative stabilities for the different tautomers have been calculated in the gas phase, including interaction with two discrete water molecules and taking into account the solvent effects by using the self-consistent reaction field theory. The role of specific and bulk contributions of solvent effect on the observable properties of the 5-methylcytosine is clarified. The amino-oxo form is the most abundant tautomer in aqueous media. A reaction pathway connecting amino-oxo and amino-hydroxy forms along the corresponding transition structures has been characterized. Good agreement between theoretical and available experimental results of harmonic vibration frequencies is found. (C) 2001 Elsevier B.V. B.V. All rights reserved.

LIMIT CYCLES of DISCONTINUOUS PIECEWISE LINEAR DIFFERENTIAL SYSTEMS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Heterodyne Interferometry Applied to the Characterization of Acousto-Electro-Optic Light Modulators

When the electro-optic and acousto-optic effects are combined into a single device, the resulting acousto-electro-optic (AEO) modulator shows improved flexibility to overcome some limitations of the individual modulators or their cascade combinations. By using optical interferometry, it is possible to investigate the AEO modulator behavior as a function of this applied voltage. By this way, a lithium niobate AEO modulator is positioned in one of the arms of a Mach-Zehnder interferometer and operates at 62 MHz frequency, which constitutes the intermediate frequency of the heterodyne interferometer. Operating the AEO modulator in the acousto-optic small diffraction efficiency regime, the photodetected signal amplitude and phase are analyzed, and the induced phase shift, transmission curve and linearity response are obtained. The experimental results show good agreement with that expected from the coupled-mode theory. The possibility of linear control of the optical phase shift by the external voltage, from 0 to 2 p radians, is demonstrated.

The aggressive behavior of Nile tilapia introduced into novel environments with variation in enrichment

Many studies show environmental enrichment is correlated with benefits to captive animals; however, one should not always assume this positive relationship given that enrichment increases the amount of resources that a territorial animal must defend and possibly affects its aggressive dynamics. In this study, we tested if environmental enrichment affects aggressive interactions in the aggressive fish Nile tilapia (Oreochromis niloticus). We compared fights staged between pairs of male tilapia of similar size (= matched in resource holding potential) in a novel arena that was either barren or enriched, to examine whether enrichment enhances territory value in line with theoretical predictions, with the potential for compromised welfare. We evaluated time elapsed until the first attack (latency), frequency of aggressive interactions and fight duration. We detected fight dynamic differences at the pair level. Higher resource value generated increased aggression but had no effect on fight duration or latency. This conclusion is in line with game theory predictions concerning resource value and contradicts the theory that enrichment of the environment will serve welfare purposes. (C) 2010 Elsevier GmbH. All rights reserved.

Stability of breathers in simple mechanical models for DNA

This work studies through the Floquet theory the stability of breathers generated by the anti-continuous limit. We used the Peyrard-Bishop model for DNA and two kinds of nonlinear potential: the Morse potential and a potential with a hump. The comparison of their stability was done in function of the coupling parameter. We also investigate the dynamic behaviour of the system in stable and unstable regions. Qualitatively, the dynamic of mobile breathers resembles DNA.

Recursive renormalization of the singlet one-pion-exchange plus point-like interactions

The subtracted kernel approach is shown to be a powerful method to be implemented recursively in scattering equations with regular plus point-like interactions. The advantages of the method allows one to recursively renormalize the potentials, with higher derivatives of the Dirac-delta, improving previous results. The applicability of the method is verified in the calculation of the 1 So nucleon-nucleon phase-shifts, when considering a potential with one-pion-exchange plus a contact interaction and its derivatives. The S-1(0) renormalization parameters are fitted to the data. The method can in principle be extended to any derivative order of the contact interaction, to higher partial waves and to coupled channels. (c) 2005 Elsevier B.V. All rights reserved.

Quantum states, thermodynamic limits, and entropy in M theory

We discuss the matching of the BPS part of the spectrum for a (super) membrane, which gives the possibility of getting the membrane's results via string calculations. In the small coupling limit of M theory the entropy of the system coincides with the standard entropy of type IIB string theory (including the logarithmic correction term). The thermodynamic behavior at a large coupling constant is computed by considering M theory on a manifold with a topology T-2 x R-9. We argue that the finite temperature partition functions (brane Laurent series for p not equal 1) associated with the BPS p-brane spectrum can be analytically continued to well-defined functionals. It means that a finite temperature can be introduced in brane theory, which behaves like finite temperature field theory. In the limit p --> 0 (point particle limit) it gives rise to the standard behavior of thermodynamic quantities.