Pedro José Steiner Neto

Abordagem de um problema médico por meio do processo de KDD com ênfase à análise exploratória dos dados

Knowledge Discovery in Databases - KDD - is a process that consists of several steps, beginning with the collection of data for the problem under analysis and ending with the interpretation and evaluation of the final results. This paper discusses the influence of exploratory data analysis on the performance of Data Mining techniques with respect to the classification of new patterns, based on its application to a medical problem, and compares the performance of these techniques in order to identify the one with the highest percentage of successes. The results of this study lead to the conclusion that, providing this analysis is done properly, it can significantly improve the performance of these techniques and serve as an important tool to optimize the end results. For the problem under study, the techniques involving a Linear Programming model and Neural Networks were the ones showing the lowest percentages of errors for the test sets, presenting good generalization capacities.

Extração de regras de classificação a partir de redes neurais para auxílio à tomada de decisão na concessão de crédito bancário

Credit-risk evaluation is a very important management science problem in the financial analysis area. Neural Networks have received a lot of attention because of their universal approximation property. They have a high predictive accuracy rate, but how they reach their decisions is not easy to understand. In this paper, we present a real-life credit-risk data set and analyzed it using the NeuroRule extraction technique and the software WEKA. The results were considered very satisfactory, reaching more than 80% of accuracy in granting or denying credit on every simulation.

Otimização no serviço de saúde no estado do Paraná: fluxo de pacientes e novas configurações hierárquicas

Neste trabalho e apresentada uma proposta para a otimizacao no servico de saude no estado do Parana com relacao ao fluxo de pacientes dentro do estado e a regionalizacao (divisao) do estado, obtendo novas configuracoes hierarquicas para o mesmo. Quanto a regionalizacao, a proposta consiste em dividir o estado em regioes menores, formadas por varias cidades, vinculadas a uma cidade sede, principal responsavel pelo atendimento no seu nivel de resolutividade. Com relacao ao fluxo de pacientes, e proposto um algoritmo que, ao mesmo tempo em que organiza as informacoes, otimiza o fluxo. Ja para a regionalizacao, fez-se uso do algoritmo branch and price, que utiliza o algoritmo de geracao de colunas em cada no de uma arvore branch and bound. A tecnica proposta apresentada para otimizar o fluxo de pacientes mostrou-se eficaz e util, pois alem de fazer o controle dos procedimentos medicos realizados em cada cidade, tambem define para qual cidade o paciente deve ser encaminhado, respeitando a divisao hierarquica do estado. Ja o algoritmo branch and price, utilizado para a otimizacao na regionalizacao do estado, e bastante interessante, pois tenta melhorar a referida divisao hierarquica do estado, levando em consideracao o numero de habitantes e o numero de procedimentos medicos de cada municipio do estado. Os resultados obtidos tem atendido as expectativas da SESA-PR.

Evidências empíricas da influência da família, mídia, escola e pares nos antecedentes e no comportamento de separação de materiais para a reciclagem

This article analyzes the influence of family, school, media and peers on knowledge, in the sense of separation and the behavior of separation of materials for recycling by university students. To this end, the review makes a theoretical connection between the last stage of consumer behavior, which includes the separation of materials for recycling, and the agents of socialization that have been studied as influences on other types of behavior. A model and seven hypotheses were proposed by the authors. The research was divided into two stages. The first is characterized as a qualitative exploratory stage. The second, quantitative stage, was conducted with 351 university students. The quantitative analysis used the structural equation modeling to verify the proposed model. The results show that the four agents influence behavior during separation of materials for recycling either directly or indirectly. The behavior is influenced directly by personal contact (family and peers). But indirectly, the school, the media and peers impinge on feelings, serving as an antecedent of behavior.

A multi-objective genetic algorithm based approach for location of grain silos in Paraná State of Brazil

Abstract The production of soybean and corn has increased steadily in Brazil, with the Parana State being the second largest producer of these grains. The increased production has now necessitated the storing facility also to be increased. Accordingly, partitioning the storage facility is a proposal to aggregate the municipalities of Parana into regions for effective transportation of the grains. Motivated by the requirement, the present work aims to organize the storage regions by aggregating the municipalities as a multi-objective graph (territory) partitioning problem with the municipalities being the nodes and roads linking them as the edges of the graph. In order to find the effective number of new silos to be constructed and their region-wise locations, maximization of the homogeneity of storage deficit and minimization of the inter-region product transportation cost from production sources to storage points are considered as two objective functions for the problem. A multi-objective genetic algorithm based results, presented here, should have a strong impact on the grain storage system management in Parana. Moreover, the proposed methodology might act as a useful grain storage management decision aiding tool in other territories.

EFEITO GOVERNO E CERTIFICAÇÃO NA INDÚSTRIA BRASILEIRA DE SOFTWARE

Este trabalho analisa o papel do Estado brasileiro como agente influenciador das estrategias de qualidade das empresas produtoras de software no Brasil. A partir dos dados coletados entre os anos de 1995-2009, conduziu-se um estudo longitudinal quantitativo e descritivo. Foram estudadas 2.229 empresas de software . Sob a perspectiva dos fundamentos da Teoria da Agencia e da Teoria dos Custos de Transacao, observa-se a conscientizacao da necessidade de certificacao no cenario internacional. A mudanca significativa no perfil das empresas pode ser observada pela adocao de modelos de certificacao para o setor, em especial o MPS.BR, especificamente desenvolvidos por agencias governamentais em parceria com universidades e entidades privadas. A capacitacao tecnologica das empresas foi obtida por meio de subsidios e apoio governamental, como incentivo a busca da competitividade nacional e internacional.

Education Quality Measured by the Classification of School Performance Using Quality Labels

Quality in education has been the subject of many debates, be it among managers in schools, in the media or in literature. However, the literature appears not to include methods or techniques for exploring databases to obtain classifications for this quality; nor is there a consensus as to the definition of “education quality”. To address these issues, this article proposes a methodology similar to the KDD (Knowledge Discovery in Databases) to classify Education Quality in schools comparatively, based on grades scored in school performance tests. For the purposes of this study, the test used was the Prova Brasil examination, which is part of the Basic Education Development Index (IDEB) used in Brazil. The methodology was applied to public municipal schools in the town of Araucária in the metropolitan district of Curitiba in Paraná State. Seventeen schools that offer elementary and junior high school education were included. All the grades of every student were considered from the early and later years at the schools. During the Data Mining stage, the main stage of the KDD process, three comparative methods were used for Pattern Recognition: Artificial Neural Networks, Support Vector Machines and Genetic Algorithms. These methods supplied satisfactory results in the classification of schools represented by way of a “Quality Label”, with Artificial Neural Networks having the best performance for the problem in question. With this quality label, educational managers can decide on which measures to adopt at all the schools to help them achieve their goals.

A Influência da autorregulação nas heurísticas e vieses utilizados no processo de tomada de decisão [doi: 10.5329/RECADM.2014026]

Entre as diferentes teorias heuristicas que visam explicar o processo decisorio, este estudo explora a falacia do jogador e a teoria da mao-quente. O objetivo deste artigo e investigar a influencia da autorregulacao afetiva nas heuristicas e vieses utilizados no processo de tomada de decisao. Foram realizados dois experimentos. No primeiro, foi avaliado se os resultados anteriores de ganhos com acoes de empresas afetavam a preferencia dos consumidores pela compra ou venda dessas acoes. Constatou-se diferenca entre generos no processo decisorio, com a ocorrencia da falacia do jogador para a amostra masculina, mas nao para a amostra feminina. O segundo experimento foi realizado com o intuito de verificar o papel da autorregulacao nestas heuristicas. Apos a inducao de autorregulacao, observou-se a ocorrencia da falacia do jogador e o vies da mao quente em algumas condicoes, indicando alteracoes nas decisoes tomadas pelos consumidores. A partir desses resultados, conclui-se que ha uma influencia significativa do estado afetivo nas tomadas de decisao e que as mulheres sao menos suscetiveis a falacia do jogador do que os homens. Keywords Autorregulacao; tomada de decisao; falacia do jogador; teoria da mao quente. THE INFLUENCE OF SELF-REGULATION IN HEURISTICS AND BIASES USED IN CONSUMER DECISION MAKING RESUMO Among the different heuristics theories that attempt to explain the decision making process, this study explores the gamblers fallacy and the hot hand theory. This paper investigates the influence of self-regulation in heuristics and biases used during consumer decision making. Two experiments were conducted. The first one assessed if results of past performance of stocks affected consumer preference to buy or sell those stocks. Results indicated a significant difference between gender in decision making, with the occurrence of the gamblers fallacy for the male sample, but not for the female sample. The second experiment investigated the role of self-regulation in the gamblers fallacy and hot hand bias. Results showed that after the induction of self-regulation, it was noticed the gamblers fallacy and the hot hand theory in some conditions, indicating changes in the decisions made by consumers. We conclude that there is a significant influence of affective state in decision making and that women are less susceptible to the gamblers fallacy than men. Palavras-Chave Self-regulation; decision making; gambler’s fallacy; hot hand theory.

A Influência da autorregulação nas heurísticas e vieses utilizados no processo de tomada de decisão

Among the different heuristics theories that attempt to explain the decision making process, this study explores the gamblers fallacy and the hot hand theory. This paper investigates the influence of self-regulation in heuristics and biases used during consumer decision making. Two experiments were conducted. The first one assessed if results of past performance of stocks affected consumer preference to buy or sell those stocks. Results indicated a significant difference between gender in decision making, with the occurrence of the gamblers fallacy for the male sample, but not for the female sample. The second experiment investigated the role of self-regulation in the gamblers fallacy and hot hand bias. Results showed that after the induction of self-regulation, it was noticed the gamblers fallacy and the hot hand theory in some conditions, indicating changes in the decisions made by consumers. We conclude that there is a significant influence of affective state in decision making and that women are less susceptible to the gamblers fallacy than men.