Previsão do índice bovespa por meio de redes neurais artificiais: uma análise comparada aos métodos tradicionais de séries de tempo

Forecast is the basis for making strategic, tactical and operational business decisions. In financial economics, several techniques have been used to predict the behavior of assets over the past decades.Thus, there are several methods to assist in the task of time series forecasting, however, conventional modeling techniques such as statistical models and those based on theoretical mathematical models have produced unsatisfactory predictions, increasing the number of studies in more advanced methods of prediction. Among these, the Artificial Neural Networks (ANN) are a relatively new and promising method for predicting business that shows a technique that has caused much interest in the financial environment and has been used successfully in a wide variety of financial modeling systems applications, in many cases proving its superiority over the statistical models ARIMA-GARCH. In this context, this study aimed to examine whether the ANNs are a more appropriate method for predicting the behavior of Indices in Capital Markets than the traditional methods of time series analysis. For this purpose we developed an quantitative study, from financial economic indices, and developed two models of RNA-type feedfoward supervised learning, whose structures consisted of 20 data in the input layer, 90 neurons in one hidden layer and one given as the output layer (Ibovespa). These models used backpropagation, an input activation function based on the tangent sigmoid and a linear output function. Since the aim of analyzing the adherence of the Method of Artificial Neural Networks to carry out predictions of the Ibovespa, we chose to perform this analysis by comparing results between this and Time Series Predictive Model GARCH, developing a GARCH model (1.1).Once applied both methods (ANN and GARCH) we conducted the results' analysis by comparing the results of the forecast with the historical data and by studying the forecast errors by the MSE, RMSE, MAE, Standard Deviation, the Theil's U and forecasting encompassing tests. It was found that the models developed by means of ANNs had lower MSE, RMSE and MAE than the GARCH (1,1) model and Theil U test indicated that the three models have smaller errors than those of a naïve forecast. Although the ANN based on returns have lower precision indicator values than those of ANN based on prices, the forecast encompassing test rejected the hypothesis that this model is better than that, indicating that the ANN models have a similar level of accuracy . It was concluded that for the data series studied the ANN models show a more appropriate Ibovespa forecasting than the traditional models of time series, represented by the GARCH model

Balanced Scorecard: fatores relevantes de sua implantação na diretoria de mercado de capitais do Banco do Brasil

Este trabalho objetiva determinar que características do corpo funcional da DIMEC (Diretoria de Mercado de Capitais do Banco do Brasil) estão associadas aos principais entraves considerados relevantes pelos funcionários da área durante a implementação do Balanced Scorecard (BSC). Pretende-se salientar como entraves tais como a falta de apoio de Tecnologia de Informação e a falta de hábito dos funcionários em lidar com indicadores não financeiros podem se relacionar com as características de interesse do corpo funcional, tais como nível hierárquico , formação acadêmica e nível de conhecimento da ferramenta BSC , de forma a influenciar na implementação do modelo. Para tanto foi realizada revisão de literatura e estudo de caso no qual figuraram, como instrumentos de coleta de dados, a aplicação de questionários e a entrevista não-estruturada através dos quais funcionários da DIMEC demonstraram as relações entre as variáveis descritas de forma a destacar fatores de relevância para o desenrolar do processo de implantação da ferramenta BSC na referida empresa

Previsão do índice bovespa por meio de redes neurais artificiais: uma análise comparada aos métodos tradicionais de séries de tempo

Forecast is the basis for making strategic, tactical and operational business decisions. In financial economics, several techniques have been used to predict the behavior of assets over the past decades.Thus, there are several methods to assist in the task of time series forecasting, however, conventional modeling techniques such as statistical models and those based on theoretical mathematical models have produced unsatisfactory predictions, increasing the number of studies in more advanced methods of prediction. Among these, the Artificial Neural Networks (ANN) are a relatively new and promising method for predicting business that shows a technique that has caused much interest in the financial environment and has been used successfully in a wide variety of financial modeling systems applications, in many cases proving its superiority over the statistical models ARIMA-GARCH. In this context, this study aimed to examine whether the ANNs are a more appropriate method for predicting the behavior of Indices in Capital Markets than the traditional methods of time series analysis. For this purpose we developed an quantitative study, from financial economic indices, and developed two models of RNA-type feedfoward supervised learning, whose structures consisted of 20 data in the input layer, 90 neurons in one hidden layer and one given as the output layer (Ibovespa). These models used backpropagation, an input activation function based on the tangent sigmoid and a linear output function. Since the aim of analyzing the adherence of the Method of Artificial Neural Networks to carry out predictions of the Ibovespa, we chose to perform this analysis by comparing results between this and Time Series Predictive Model GARCH, developing a GARCH model (1.1).Once applied both methods (ANN and GARCH) we conducted the results' analysis by comparing the results of the forecast with the historical data and by studying the forecast errors by the MSE, RMSE, MAE, Standard Deviation, the Theil's U and forecasting encompassing tests. It was found that the models developed by means of ANNs had lower MSE, RMSE and MAE than the GARCH (1,1) model and Theil U test indicated that the three models have smaller errors than those of a naïve forecast. Although the ANN based on returns have lower precision indicator values than those of ANN based on prices, the forecast encompassing test rejected the hypothesis that this model is better than that, indicating that the ANN models have a similar level of accuracy . It was concluded that for the data series studied the ANN models show a more appropriate Ibovespa forecasting than the traditional models of time series, represented by the GARCH model

Indústria cultural e forró eletrônico no Rio Grande do Norte

The present study aimed to understand how and to what extent the electronic forró, currently hegemonic in the music market in the state of Rio Grande do Norte, establishes and maintains relations of domination in the social contexts in which it is produced, transmitted and received. Based, in significant form-content, on the writings of the first generation of theorists of the so-called Frankfurt School (Critical Theory), particularly with Theodor W. Adorno, and systematically using the contributions of the Cultural Studies (from the Centre for Contemporary Cultural Studies of Birmingham) and of the sociology of Pierre Bourdieu, this study aimed to perform, in the fertile intersection of these references, a critical possibility of interpretation of the electronic forró predominantly spread in the state of Rio Grande do Norte. To this end, aiming at a better apprehension of the so-called capital circuits/culture circuits , this study resulted from a qualitative investment of research, based on structured interviews with musicians, entrepreneurs of the sector and music consumers, as well as on the analysis of the themes contained in the official discography of the electronic forró band called Garota Safada (Shameless Girl). As a general empirical conclusion, it was possible to infer that far from the significant presence of domination or mere prevalence of oppositions, there is a relational pluralism of forms of domination and ways of resistances present in the production and consumption of electronic forró, regardless of gender, age, income, education or place of residence. However, the artifices of the cultural industry has been shown to be efficient: from large-scale businessmen to small producers enabled by the so-called open markets . The currentness of the concept of cultural industry is based on the idea that its products are offered systematically (the systematic insistence of everything to everyone) and on the notion that its production primarily meets the administrative criteria of control over the effects on the receiver (capacity of prescription of desires). Thus, the Adornian reflection on the pseudo-individualization leads to the inference that even in some of the most apparent ways of negotiation and/or refusal regarding the consumption of forró, certain behaviors of the cultural industry still prevail both in the very (re)interpretation of the forró and in the choice of other music genres also standardized, rationalized and massified. Therefore, despite the absence of cause-effect relation and the recognition of the popular capacity of re-elaboration and contestation of the media consumption, some world views prevailing in relation to the electronic forró establish or, at least, support some hegemonic ideologies, especially those concerning the life style, consumption and genre relations (fun by all means). Therefore, due the massification of certain songs, some ways of dissemination of values, beliefs and feelings are potentially experienced from the electronic forró. So, it is presumable that in the current advance of the process of semiformation (Halbbildung), the habitus of a part of the youth from the state of Rio Grande do Norte reinforces and is reinforced by the centrality of the trinomial fun, love and sex present in the songs, emphasized in some constructive practices of sense and in certain flows of social significance

Turismo, capital social e produção do espaço: uma leitura a partir do município de Natal/RN no período de 1980 a 2012

Nowadays, there is a tourism phase in the city of Natal/RN called internationalization of tourism , which shows a tourism model with a planning and an administration, based on the needs of the visitors. Such process shows that the production as well as the reproduction of the city spaces with the goal of favor tourism excludes of its composition the effective participation of local subjects. Thus, the research is a result of the perception of tourism as an activity with a meaningful power of transformation of the social and natural space taking into account the low participation of the residents in the decisions of the tourism activities in the city of Natal/RN. Despite that reality, it is possible to note Natal that civil society, starts to mobilize its citizens trying to develop collective actions to low the negative impacts caused by the bad planning as wells not efficient tourism administration, trying to put in action the right of the local population to take part in the decisions of the city activities. Having this panorama as background, this paper aims at investigating in which way the mobilizing action of the social capital in Natal has contributed to change the spatial production which is part of the process of expansion of tourism in Natal/RN? The research presents a temporal picture which starts in the year of 1980, when occurs the first effective state intervention aiming to develop tourism in the capital, taking into account an analysis of 2012. Concerning the spatial picture, the research investigates the beaches of Natal which concentrates criteria and actions such as: visitation, tourism appeal and focus of investments, highlighting the following beaches: Ponta Negra, Areia Preta, Praia dos Artistas, Praia do Meio, Praia do Forte and Redinha. This study is of a descriptive and exploratory nature concerning its goals. With respect to the treatment of its object it is a qualitative research. The data was collected through structural interviews, with open questions. Regarding the methodological choices, it was used the content analysis proposed as well as the collective discursive subject methodology. The results show that there´s not yet in Natal a meaningful social capital related to tourism, capable to change the spatial production related to the activity. It should be stressed that Natal social capital presents difficulties concerning the incentive to trust, spontaneous cooperation and the civic participation, which are the foundation for the development of an effective social capital, which makes it harder for a more expressive articulation in the reality in Natal/RN. It should be stressed, as an answer to the research questions, that tourism in Natal/RN is represented by social and spatial segregation. In other words it emphasizes mainly the action of hegemonic agents (State and market), leaving little room for the participation of society. It can be noticed that the actions related to tourism in Natal keeps the popular participation out of the way. Thus, it can be said that the social capital in Natal/RN does not yet contribute to a more fair spatial production related to the expansion of the tourism as well as the well being of the population of Natal/RN. In conclusion, it should be taken into account that this participation do exists but not in a meaningful way. In other words, it´s not enough yet to cause meaningful changes in the actions which tourism needs nowadays in Natal/RN