530 resultados para Judgmental heuristics


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O modelo racional de decisão tem sido objeto de estudo constante na academia de vários países, contribuindo para evolução do ser racional como importante tomador de decisão. A evolução destes estudos tem aberto questionamentos quanto à capacidade de racionalidade que temos como tomadores de decisão, deleitando assim em várias teorias novas que pesquisam estas limitações no decidir. Especialmente aplicadas a teorias econômicas, estudos como Inteligência Artificial, Contabilidade Mental, Teoria dos Prospectos, Teoria dos Jogos entre outras se destacam neste cenário de estudo das finanças comportamentais. A contabilidade como ferramenta de apoio as decisões financeiras ocupa posição de destaque. Esta tem em seu escopo de trabalho normas (aquilo que deveria ser feito) que regulam sua atuação, em alguns casos esta regulamentação não é precisa em suas especificações, deixando janelas que levam seus profissionais a erros de interpretação. A imprecisão contábil pode causar viés em suas classificações. Os profissionais, deparados com este legado podem se utilizar de heurísticas para interpretar da melhor maneira possível os acontecimentos que são registrados na contabilidade. Este trabalho tem a intenção de análise de alguns pontos que consideramos importantes quando temos imprecisão contábil, respondendo as seguintes perguntas: a imprecisão de normas contábeis causa viés na decisão? O profissional que se depara com imprecisão contábil se utiliza de Heurística para decidir? Quais os erros mais comuns de interpretação sob incerteza contábil? Para que o assunto fosse abordado com imparcialidade de maneira a absorver retamente quais são as experiências dos profissionais que atuam na área contábil, foi elaborado um questionário composto por uma situação possível que leva o respondente a um ambiente de tomada de decisões que envolva a prática contábil. O questionário era dividido em duas partes principais, com a preocupação de identificar através das respostas se existe imprecisão contábil (sob a luz do princípio da prudência) e quais heurísticas que os respondentes se utilizam com mais freqüência, sendo o mesmo aplicado em profissionais que atuam na área contábil e que detenham experiências profissionais relacionadas à elaboração, auditoria ou análise de demonstrações contábeis. O questionário aplicado na massa respondente determinou, através das respostas, que existe, segundo os profissionais, interpretações diferentes para os mesmos dados, caracterizando assim zona cinzenta, segundo Penno (2008), ou seja, interpretações que podem ser mais agressivas ou mais conservadoras conforme a interpretação do profissional. Já quanto às estratégias simplificadoras, ou heurísticas, que causam algum tipo de enviesamento no processo decisório, alguns foram identificadas como: associações pressupostas, interpretação errada da chance, regressão a media e eventos disjuntivos e eventos conjuntivos, que reforçam a pesquisa dando indícios de que os respondentes podem estar tomando decisões enviesadas. Porém, não se identificou no estudo tomada de decisões com enviesamentos como recuperabilidade e insensibilidades ao tamanho da amostra. Ao final do estudo concluímos que os respondentes têm interpretações diferenciadas sobre o mesmo assunto, mesmo sob a luz do princípio contábil da prudência, e ainda se utilizam de estratégias simplificadoras para resolverem assuntos quotidianos.

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Decision makers often use ‘rules of thumb’, or heuristics, to help them handling decision situations (Kahneman and Tversky, 1979b). Those cognitive shortcuts are taken by the brain to cope with complexity and time limitation of decisions, by reducing the burden of information processing (Hodgkinson et al, 1999; Newell and Simon, 1972). Although crucial for decision-making, heuristics come at the cost of occasionally sending us off course, that is, make us fall into judgment traps (Tversky and Kahneman, 1974). Over fifty years of psychological research has shown that heuristics can lead to systematic errors, or biases, in decision-making. This study focuses on two particularly impactful biases to decision-making – the overconfidence and confirmation biases. A specific group – top management school students and recent graduates - were subject to classic experiments to measure their level of susceptibility to those biases. This population is bound to take decision positions at companies, and eventually make decisions that will impact not only their companies but society at large. The results show that this population is strongly biased by overconfidence, but less so to the confirmation bias. No significant relationship between the level of susceptibility to the overconfidence and to the confirmation bias was found.

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Nota: A autora agradece à Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) pela concessão de bolsa de estudos para o desenvolvimento deste projeto de pesquisa.

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O presente trabalho tem por objetivo subsidiar o investidor de Fundos de Investimento Imobiliário na escolha de uma carteira de aplicação de FIIs, visando obter performance igual ou superior ao índice de referência do setor (IFIX). Tal subsídio é constituído, inicialmente, por uma metodologia que considera que o conceito de Carteira Eficiente (Risco/Retorno) preconizada por Markowitz pode trabalhar em conjunto com a dimensão do conceito das Finanças Comportamentais, liderada por Daniel Kahneman, constituindo as bases de orientação do investidor. Acrescentamos o caminho metodológico com as indicações, sugeridas por Bazerman e Moore, no processo de tomada de decisão, que reduza os efeitos de heurísticas e vieses.

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The Behavioral Finance develop as it is perceived anomalies in these markets efficient. This fields of study can be grouped into three major groups: heuristic bias, tying the shape and inefficient markets. The present study focuses on issues concerning the heuristics of representativeness and anchoring. This study aimed to identify the then under-reaction and over-reaction, as well as the existence of symmetry in the active first and second line of the Brazilian stock market. For this, it will be use the Fuzzy Logic and the indicators that classify groups studied from the Discriminant Analysis. The highest present, indicator in the period studied, was the Liabilities / Equity, demonstrating the importance of the moment to discriminate the assets to be considered "winners" and "losers." Note that in the MLCX biases over-reaction is concentrated in the period of financial crisis, and in the remaining periods of statistically significant biases, are obtained by sub-reactions. The latter would be in times of moderate levels of uncertainty. In the Small Caps the behavioral responses in 2005 and 2007 occur in reverse to those observed in the Mid-Large Cap. Now in times of crisis would have a marked conservatism while near the end of trading on the Bovespa speaker, accompanied by an increase of negotiations, there is an overreaction by investors. The other heuristics in SMLL occurred at the end of the period studied, this being a under-reaction and the other a over-reaction and the second occurring in a period of financial-economic more positive than the first. As regards the under / over-reactivity in both types, there is detected a predominance of either, which probably be different in the context in MLCX without crisis. For the period in which such phenomena occur in a statistically significant to note that, in most cases, such phenomena occur during the periods for MLCX while in SMLL not only biases are less present as there is no concentration of these at any time . Given the above, it is believed that while detecting the presence of bias behavior at certain times, these do not tend to appear to a specific type or heuristics and while there were some indications of a seasonal pattern in Mid- Large Caps, the same behavior does not seem to be repeated in Small Caps. The tests would then suggest that momentary failures in the Efficient Market Hypothesis when tested in semistrong form as stated by Behavioral Finance. This result confirms the theory by stating that not only rationality, but also human irrationality, is limited because it would act rationally in many circumstances

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It dares to ensure that the Constitution of the Republic strengthened the rights of personality. No longer considering the denial of protection to intangible rights, against the imperative command coming from the art. 5 ° of our highest law, relevant to items V and X. Overlooking these emerge with precision, those rights of personality. Innocuous have been isolated attempts of the opposition to this constitutional protection. Deny it, or rather to restrict it, as it has done insignificant part of the doctrine and isolated judgmental pronouncements, no longer prove appropriate. Today, more than before, there is pointed out that if the human being has personal rights acquired from the design, adding to this other identity elements that allow the projection of a particular social personality. Such rights, it is worth mentioning, there are bases on the principle of human dignity that is considered general provision for the protection of personality. Based on the demonstration of this fact, after climbing into the general theory of personal rights and demonstrate the legal protection that has been present in his favor, it is hoped will, general objective, to show the effectiveness of this constitutional protection. At that point, will be reserved for special to the procedural tools that it has made a decisive contribution to the realization and effectiveness of the rights of the personality, a reality that must be imposed for the benefit of the dignity of the human person, presented here as basic foundation of the Democratic State of Law. The brazilian legal system provides the normative basis needed to provide an adequate protection to personality, from the general clause of the protection of the personality. For the achievement of its effectiveness, however, is an important update methodological and cultural of the Right as well as an effective deployment of public policies and private ensuring a better quality of life for citizens

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This Thesis deals with the usability in some sites of hotels placed in a specific region of Brazil. Usability is the property of a site that shows how it allows the user get all information available without a large effort and in a clear and objective way. A questionnaire was used as a tool to value, by the common user perspective, navigation, on line reservation simulation, appreciation of the available content and, by this way, an easiness in the interaction site-users. As a result, it is possible to say that, considering all material analyzed, those sites that present usability criterion are more interactive and dynamic, demonstrating an easy navigation in a users view. By other side, it was possible to note that, about heuristics used in the search, the most of the websites demonstrated a deficiency in questions as firmness, user control and how to avoid mistakes. There was still valued as deficiency by the most of users in websites the general characters and the view of user. It was presented, seeing general characters, that a big part of the websites needs tools that can make user rapidly find what looks for. It was yet possible to see that users don't believe in secret when websites ask them some information. This is a point that needs to be appreciated because it causes some insecurity during navigation

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The SONET/SDH Ring Assignment Problem (PALAS) treats to group localities in form of some rings, being respected the traffic's limitations of the equipment. Each ring uses a DXC (Digital Cross Connect) to make the communication with the others, being the DXC the equipment most expensive of the net, minimizing the number total of rings, will minimize the total net cost, problem's objective . This topology in rings provides a bigger capacity of regeneration. The PALAS is a problem in Combinatorial Optimization of NP-hard Class. It can be solved through Heuristics and Metaheuristics. In this text, we use Taboo Search while we keep a set of elite solutions to be used in the formation of a part of the collection of vocabulary's parts that in turn will be used in the Vocabulary Building. The Vocabulary Building will be started case Taboo Search does not reach the best solution for the instance. Three approaches had been implemented: one that only uses vocabulary's parts deriving of Taboo Search, one that it only uses vocabulary's parts randomly generated and a last one that it uses half come of the elite and half randomly generated

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This paper aims to propose a hybrid meta-heuristics for the Heterogeneous Fleet Vehicle Routing Problem (HVRP), which is a combinatorial optimization problem NP-hard, and is characterized by the use of a limited fleet consists of different vehicles with different capacities. The hybrid method developed makes use of a memetic algorithm associated with the component optimizer Vocabulary Building. The resulting hybrid meta-heuristic was implemented in the programming language C + + and computational experiments generated good results in relation to meta-heuristic applied in isolation, proving the efficiency of the proposed method.

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This research aims to investigate the evolution presented during three decades (1980, 1990 and 2000) of using the tools of Operations Research (OR) as a suport to decision making in Production Operation Management (POM). Hypothesis tests were made to verify the proportional growth of a given area over the decades to the detriment of the areas of facility layout, capacity planning, production scheduling and inventory management. Six journals were selected and from them more than 800 articles were used for classification and analysis in the grounds of review. It also discussed possible ways for future research and comparisons are made with other papers of literature review. As a result, it was found that areas of heuristics and simulation showed a greater quantity of contributions in all POM areas of this study

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Worldwide, the demand for transportation services for persons with disabilities, the elderly, and persons with reduced mobility have increased in recent years. The population is aging, governments need to adapt to this reality, and this fact could mean business opportunities for companies. Within this context is inserted the Programa de Acessibilidade Especial porta a porta PRAE, a door to door public transportation service from the city of Natal-RN in Brazil. The research presented in this dissertation seeks to develop a programming model which can assist the process of decision making of managers of the shuttle. To that end, it was created an algorithm based on methods of generating approximate solutions known as heuristics. The purpose of the model is to increase the number of people served by the PRAE, given the available fleet, generating optimized schedules routes. The PRAE is a problem of vehicle routing and scheduling of dial-a-ride - DARP, the most complex type among the routing problems. The validation of the method of resolution was made by comparing the results derived by the model and the currently programming method. It is expected that the model is able to increase the current capacity of the service requests of transport

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The problems of combinatory optimization have involved a large number of researchers in search of approximative solutions for them, since it is generally accepted that they are unsolvable in polynomial time. Initially, these solutions were focused on heuristics. Currently, metaheuristics are used more for this task, especially those based on evolutionary algorithms. The two main contributions of this work are: the creation of what is called an -Operon- heuristic, for the construction of the information chains necessary for the implementation of transgenetic (evolutionary) algorithms, mainly using statistical methodology - the Cluster Analysis and the Principal Component Analysis; and the utilization of statistical analyses that are adequate for the evaluation of the performance of the algorithms that are developed to solve these problems. The aim of the Operon is to construct good quality dynamic information chains to promote an -intelligent- search in the space of solutions. The Traveling Salesman Problem (TSP) is intended for applications based on a transgenetic algorithmic known as ProtoG. A strategy is also proposed for the renovation of part of the chromosome population indicated by adopting a minimum limit in the coefficient of variation of the adequation function of the individuals, with calculations based on the population. Statistical methodology is used for the evaluation of the performance of four algorithms, as follows: the proposed ProtoG, two memetic algorithms and a Simulated Annealing algorithm. Three performance analyses of these algorithms are proposed. The first is accomplished through the Logistic Regression, based on the probability of finding an optimal solution for a TSP instance by the algorithm being tested. The second is accomplished through Survival Analysis, based on a probability of the time observed for its execution until an optimal solution is achieved. The third is accomplished by means of a non-parametric Analysis of Variance, considering the Percent Error of the Solution (PES) obtained by the percentage in which the solution found exceeds the best solution available in the literature. Six experiments have been conducted applied to sixty-one instances of Euclidean TSP with sizes of up to 1,655 cities. The first two experiments deal with the adjustments of four parameters used in the ProtoG algorithm in an attempt to improve its performance. The last four have been undertaken to evaluate the performance of the ProtoG in comparison to the three algorithms adopted. For these sixty-one instances, it has been concluded on the grounds of statistical tests that there is evidence that the ProtoG performs better than these three algorithms in fifty instances. In addition, for the thirty-six instances considered in the last three trials in which the performance of the algorithms was evaluated through PES, it was observed that the PES average obtained with the ProtoG was less than 1% in almost half of these instances, having reached the greatest average for one instance of 1,173 cities, with an PES average equal to 3.52%. Therefore, the ProtoG can be considered a competitive algorithm for solving the TSP, since it is not rare in the literature find PESs averages greater than 10% to be reported for instances of this size.

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The frequency selective surfaces, or FSS (Frequency Selective Surfaces), are structures consisting of periodic arrays of conductive elements, called patches, which are usually very thin and they are printed on dielectric layers, or by openings perforated on very thin metallic surfaces, for applications in bands of microwave and millimeter waves. These structures are often used in aircraft, missiles, satellites, radomes, antennae reflector, high gain antennas and microwave ovens, for example. The use of these structures has as main objective filter frequency bands that can be broadcast or rejection, depending on the specificity of the required application. In turn, the modern communication systems such as GSM (Global System for Mobile Communications), RFID (Radio Frequency Identification), Bluetooth, Wi-Fi and WiMAX, whose services are highly demanded by society, have required the development of antennas having, as its main features, and low cost profile, and reduced dimensions and weight. In this context, the microstrip antenna is presented as an excellent choice for communications systems today, because (in addition to meeting the requirements mentioned intrinsically) planar structures are easy to manufacture and integration with other components in microwave circuits. Consequently, the analysis and synthesis of these devices mainly, due to the high possibility of shapes, size and frequency of its elements has been carried out by full-wave models, such as the finite element method, the method of moments and finite difference time domain. However, these methods require an accurate despite great computational effort. In this context, computational intelligence (CI) has been used successfully in the design and optimization of microwave planar structures, as an auxiliary tool and very appropriate, given the complexity of the geometry of the antennas and the FSS considered. The computational intelligence is inspired by natural phenomena such as learning, perception and decision, using techniques such as artificial neural networks, fuzzy logic, fractal geometry and evolutionary computation. This work makes a study of application of computational intelligence using meta-heuristics such as genetic algorithms and swarm intelligence optimization of antennas and frequency selective surfaces. Genetic algorithms are computational search methods based on the theory of natural selection proposed by Darwin and genetics used to solve complex problems, eg, problems where the search space grows with the size of the problem. The particle swarm optimization characteristics including the use of intelligence collectively being applied to optimization problems in many areas of research. The main objective of this work is the use of computational intelligence, the analysis and synthesis of antennas and FSS. We considered the structures of a microstrip planar monopole, ring type, and a cross-dipole FSS. We developed algorithms and optimization results obtained for optimized geometries of antennas and FSS considered. To validate results were designed, constructed and measured several prototypes. The measured results showed excellent agreement with the simulated. Moreover, the results obtained in this study were compared to those simulated using a commercial software has been also observed an excellent agreement. Specifically, the efficiency of techniques used were CI evidenced by simulated and measured, aiming at optimizing the bandwidth of an antenna for wideband operation or UWB (Ultra Wideband), using a genetic algorithm and optimizing the bandwidth, by specifying the length of the air gap between two frequency selective surfaces, using an optimization algorithm particle swarm

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In this work we present a new clustering method that groups up points of a data set in classes. The method is based in a algorithm to link auxiliary clusters that are obtained using traditional vector quantization techniques. It is described some approaches during the development of the work that are based in measures of distances or dissimilarities (divergence) between the auxiliary clusters. This new method uses only two a priori information, the number of auxiliary clusters Na and a threshold distance dt that will be used to decide about the linkage or not of the auxiliary clusters. The number os classes could be automatically found by the method, that do it based in the chosen threshold distance dt, or it is given as additional information to help in the choice of the correct threshold. Some analysis are made and the results are compared with traditional clustering methods. In this work different dissimilarities metrics are analyzed and a new one is proposed based on the concept of negentropy. Besides grouping points of a set in classes, it is proposed a method to statistical modeling the classes aiming to obtain a expression to the probability of a point to belong to one of the classes. Experiments with several values of Na e dt are made in tests sets and the results are analyzed aiming to study the robustness of the method and to consider heuristics to the choice of the correct threshold. During this work it is explored the aspects of information theory applied to the calculation of the divergences. It will be explored specifically the different measures of information and divergence using the Rényi entropy. The results using the different metrics are compared and commented. The work also has appendix where are exposed real applications using the proposed method

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Several methods of mobile robot navigation request the mensuration of robot position and orientation in its workspace. In the wheeled mobile robot case, techniques based on odometry allow to determine the robot localization by the integration of incremental displacements of its wheels. However, this technique is subject to errors that accumulate with the distance traveled by the robot, making unfeasible its exclusive use. Other methods are based on the detection of natural or artificial landmarks present in the environment and whose location is known. This technique doesnt generate cumulative errors, but it can request a larger processing time than the methods based on odometry. Thus, many methods make use of both techniques, in such a way that the odometry errors are periodically corrected through mensurations obtained from landmarks. Accordding to this approach, this work proposes a hybrid localization system for wheeled mobile robots in indoor environments based on odometry and natural landmarks. The landmarks are straight lines de.ned by the junctions in environments floor, forming a bi-dimensional grid. The landmark detection from digital images is perfomed through the Hough transform. Heuristics are associated with that transform to allow its application in real time. To reduce the search time of landmarks, we propose to map odometry errors in an area of the captured image that possesses high probability of containing the sought mark