Análise da sobre-reação e sub-reação nos ativos de primeira e segunda lina do mercado acionário brasileiro

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

Atuação dos profissionais de enfermagem durante o processo transfusional na UTI de um hostital universitário

Prospective descriptive study with quantitative approach, which aimed to analyze the relationship of the knowledge of Nurses and conduct assistance during the process of transfusion, to patients in the ICU of a university hospital in Natal-RN. The sample consisted of 27 professionals from the nursing staff (5 nurses and 22 nursing technicians), climbing in the ICU during the period of data collection. Data collection was through a questionnaire and structured form of observation, in addition to consulting the diary. The results were organized in SPSS 15.0, tabulated, cathegorized and analyzed by descriptive and inferential statistics. The results show a young population, aged between 21 and 32 years (63.0%), female (85.2%). Among those surveyed were the main type of stock, mostly technical, nursing (ρ= 0006), which have little time to experience - up to 2 years (ρ= 0008), did not know the DRC in 153 (ρ= 0019), held greater number of pipelines care in blood (ρ= 0018), the non-participation in training and feel informed about the process of transfusion, showed no significant differences. As for officials, highlighted only the time to experience more than 2 years, carrying out fewer procedures and feel informed about the blood. As for the pipes during the transfusion process, I found that the majority of pipes observed in both the stock and the staff were inadequate, with predominance in the first, both in the pursuit of conduct regarding the shortfall. The averages of inappropriate conduct, predominantly developed by stock, were higher in all stages for appropriate conduct. Analyzing the knowledge about the disease process, the stock market were those who had lower scores of knowledge in three stages. As the relationship between the pipes care and knowledge, we see that at all stages of the process of transfusion inadequate knowledge of the averages were higher, taking a significant difference in the stages pre-transfusion (ρ= 0012). When analyzing the average of pipes behind, we see that in inappropriate conduct were significantly higher (ρ= 0031), who had searched in inadequate knowledge. As for the frequency of total procedures performed, we found a significant predominance (ρ= 0049) of inappropriate conduct (88.9%) of which 81.5% were developed by professionals who had inadequate knowledge, showing moderate correlation (r = 0,516) and odds ratio of 2,750 times the development of inappropriate conduct in trade with inadequate knowledge. We conclude that the professionals surveyed, especially the technicians of nursing stock, showed serious deficiencies with regard to the development of pipelines and knowledge of the transfusion process, showing the inadequacy to develop this therapy. Facing the foregoing, we accept the alternative hypothesis proposed in the study, because we show that the inadequacy of knowledge about the process of transfusion influence in inappropriate conduct implemented by the nursing staff in ICU.

The gradually truncated Levy flight for systems with power-law distributions

Power-law distributions have been observed in various economical and physical systems. Levy flights have infinite variance which discourage a physical approach. We introduce a class of stochastic processes, the gradually truncated Levy flight in which large steps of a Levy flight are gradually eliminated. It has finite variance and the system can be analyzed in a closed form. We applied the present method to explain the distribution of a particular economical index. The present method can be applied to describe time series in a variety of fields, i.e. turbulent flow, anomalous diffusion, polymers, etc. (C) 1999 Elsevier B.V. B.V. All rights reserved.

The gradually truncated Lévy flight: Stochastic process for complex systems

Power-law distributions, i.e. Levy flights have been observed in various economical, biological, and physical systems in high-frequency regime. These distributions can be successfully explained via gradually truncated Levy flight (GTLF). In general, these systems converge to a Gaussian distribution in the low-frequency regime. In the present work, we develop a model for the physical basis for the cut-off length in GTLF and its variation with respect to the time interval between successive observations. We observe that GTLF automatically approach a Gaussian distribution in the low-frequency regime. We applied the present method to analyze time series in some physical and financial systems. The agreement between the experimental results and theoretical curves is excellent. The present method can be applied to analyze time series in a variety of fields, which in turn provide a basis for the development of further microscopic models for the system. © 2000 Elsevier Science B.V. All rights reserved.

Perfil do crédito à pessoa jurídica no Brasil entre 1994 e 2007

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um estudo sobre o mercado acionário: a abordagem tradicional vs. a abordagem complexa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Distribuição estatística de um indexo econômico em mercado emergente - Bolsa de valores de São Paulo (IBOVESPA)

Pós-graduação em Física - IGCE

Verificação e análise dos fatos estilizados no mercado de ações brasileiro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Previsão de séries temporais financeiras por meio de redes neurais dinâmicas e processos de transformação de dados: uma abordagem empírico-comparativa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aplicação de um sistema de Inferência Fuzzy de suporte à decisão para estimação de valores de ações cotadas na Bolsa de Valores de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estimativa do custo médio ponderado de capital em produtos agrícolas

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Construção de conhecimento em governança corporativa: estudo sobre a criação de valor para tomada de decisão de investidores no mercado de capitais

Pós-graduação em Ciência da Informação - FFC

Mercado de ações brasileiro: uma investigação empírica sobre suas relações de longo prazo e de precedência temporal pré-crise de 2008

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