Determining appropriate approaches for using data in feature selection

Feature selection is increasingly important in data analysis and machine learning in big data era. However, how to use the data in feature selection, i.e. using either ALL or PART of a dataset, has become a serious and tricky issue. Whilst the conventional practice of using all the data in feature selection may lead to selection bias, using part of the data may, on the other hand, lead to underestimating the relevant features under some conditions. This paper investigates these two strategies systematically in terms of reliability and effectiveness, and then determines their suitability for datasets with different characteristics. The reliability is measured by the Average Tanimoto Index and the Inter-method Average Tanimoto Index, and the effectiveness is measured by the mean generalisation accuracy of classification. The computational experiments are carried out on ten real-world benchmark datasets and fourteen synthetic datasets. The synthetic datasets are generated with a pre-set number of relevant features and varied numbers of irrelevant features and instances, and added with different levels of noise. The results indicate that the PART approach is more effective in reducing the bias when the size of a dataset is small but starts to lose its advantage as the dataset size increases

REFLEXÕES SOBRE O FAZER MODELAGEM NO CONTEXTO DA EDUCAÇÃO BÁSICA REFLECTIONS ON DOING MODELING IN THE CONTEXT OF BASIC EDUCATION

Resumo: Esse artigo propõe reflexões a respeito da Modelagem Matemática enquanto prática no âmbito da Educação Matemática em nível do Ensino Fundamental. A partir de relatos de experiências vividas nesse contexto, procuramos problematizar o fazer Modelagem Matemática enfatizando a participação ativa das tecnologias (mídias) nos processos de aprendizagem. Acrescentamos que a presença da Modelagem Matemática enquanto prática nesse nível de ensino, tanto oferece possibilidades às demandas que se apresentam à Educação Matemática na sociedade altamente tecnológica em que vivemos, como impõe desafios e superações aos educadores matemáticos que a assumem, uma vez que configura um movimento a partir de uma zona de conforto em direção a uma zona de risco. Palavras-chaves: Modelagem Matemática, Seres-humanos-com-mídias, Internet, Paradigma do Exercício. Abstract: This article proposes reflections about mathematical modelling while practice in the context of mathematics education at elementary school level. From reports of experiences in this context, we seek to discuss doing mathematical modeling with emphasis on the active participation of technologies (media) in the learning processes. We add that the presence of mathematical modelling while practice at this level of education, both offers possibilities to the demands presented to the mathematics education in highly technological society we live in, as it imposes challenges and overruns to mathematical educators that assume, once that configures a movement from a comfort zone in a risk zone. Keywords: Mathematical Modelling, Human beings-with-media, Internet, Paradigm of exercise

"Sound attacks": a case report of migraine with hearing aura

IntroductionMigraine with aura is less frequent than the subtype form without aura. Normally, auras are typically manifested visual symptoms, but it is possible to have an auditory and olfactory complains as aura symptomatology.Case reportAn 8-year-old boy with family cases of migraine, complained of auditory hallucination episodes, since he was 5 years-old, with a duration of 10 to 20 minutes, followed by cure with intense photophobia and nausea. He called these episodes as "sound attacks". The frequency of the crises ranges from 4 to 5 episodes per month, with the maximum of 11 episodes in one month.Neurological examination was normal. He performed angio-MRI of skull and EEG, without any changes. Treatment was initiated with 250 mg sodium divalproate at night with reduction of events, already in the first month, for 2 to 3 episodes per month. The medication was adjusted for 500 mg of sodium divalproate with a good result, not presenting new episodes in the last 2 months.ConclusionWe report a case of migraine crises preceded by auditory aura, in a boy of 8 years. This is a rare and extremely interesting presentation of migraine, with great improvement after the prophylactic treatment.IntroductionMigraine with aura is less frequent than the subtype form without aura. Normally, auras are typically manifested visual symptoms, but it is possible to have an auditory and olfactory complains as aura symptomatology.Case reportAn 8-year-old boy with family cases of migraine, complained of auditory hallucination episodes, since he was 5 years-old, with a duration of 10 to 20 minutes, followed by cure with intense photophobia and nausea. He called these episodes as "sound attacks". The frequency of the crises ranges from 4 to 5 episodes per month, with the maximum of 11 episodes in one month.Neurological examination was normal. He performed angio-MRI of skull and EEG, without any changes. Treatment was initiated with 250 mg sodium divalproate at night with reduction of events, already in the first month, for 2 to 3 episodes per month. The medication was adjusted for 500 mg of sodium divalproate with a good result, not presenting new episodes in the last 2 months.ConclusionWe report a case of migraine crises preceded by auditory aura, in a boy of 8 years. This is a rare and extremely interesting presentation of migraine, with great improvement after the prophylactic treatment

Uma experiência vivida com estudantes do ensino médio: reflexões sobre Educação Financeira à luz da Educação Matemática Crítica

Esse artigo busca compartilhar com a comunidade de educadores matemáticos, algumas reflexões a respeito da Educação Financeira que temos praticado e pesquisado de forma colaborativa no contexto da Educação Básica. Para tanto, relatamos uma experiência desenvolvida com alunos do segundo ano do Ensino Médio de uma escola pública da cidade do Rio de Janeiro, na qual puderam refletir a respeito das compras por meio do uso de cartões de crédito, com ênfase na matemática em ação no cálculo dos juros de refinanciamento. Essa atividade serviu de pano de fundo às nossas reflexões, a partir das quais pudemos tanto descortinar possibilidades como considerar incertezas relevantes ao desenvolvimento da Educação Financeira que temos praticado e pesquisado, segundo as preocupações da Educação Matemática Crítica

Hybrid multicriteria fuzzy classification of network traffic patterns, anomalies, and protocols

© 2017, Springer-Verlag London Ltd., part of Springer Nature. Traffic classification in computer networks has very significant roles in network operation, management, and security. Examples include controlling the flow of information, allocating resources effectively, provisioning quality of service, detecting intrusions, and blocking malicious and unauthorized access. This problem has attracted a growing attention over years and a number of techniques have been proposed ranging from traditional port-based and payload inspection of TCP/IP packets to supervised, unsupervised, and semi-supervised machine learning paradigms. With the increasing complexity of network environments and support for emerging mobility services and applications, more robust and accurate techniques need to be investigated. In this paper, we propose a new supervised hybrid machine-learning approach for ubiquitous traffic classification based on multicriteria fuzzy decision trees with attribute selection. Moreover, our approach can handle well the imbalanced datasets and zero-day applications (i.e., those without previously known traffic patterns). Evaluating the proposed methodology on several benchmark real-world traffic datasets of different nature demonstrated its capability to effectively discriminate a variety of traffic patterns, anomalies, and protocols for unencrypted and encrypted traffic flows. Comparing with other methods, the performance of the proposed methodology showed remarkably better classification accuracy

Consequences Of On-Track Competition In Railways By Use Of Simulations

Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne

The First Bromeligenous Species of Dendropsophus (Anura: Hylidae) from Brazil\u27s Atlantic Forest

We describe a new treefrog species of Dendropsophus collected on rocky outcrops in the Brazilian Atlantic Forest. Ecologically, the new species can be distinguished from all known congeners by having a larval phase associated with rainwater accumulated in bromeliad phytotelms instead of temporary or lentic water bodies. Phylogenetic analysis based on molecular data confirms that the new species is a member of Dendropsophus; our analysis does not assign it to any recognized species group in the genus. Morphologically, based on comparison with the 96 known congeners, the new species is diagnosed by its small size, framed dorsal color pattern, and short webbing between toes IV-V. The advertisement call is composed of a moderate-pitched two-note call (~5 kHz). The territorial call contains more notes and pulses than the advertisement call. Field observations suggest that this new bromeligenous species uses a variety of bromeliad species to breed in, and may be both territorial and exhibit male parental care

Appendix I: Specimens examined

Three new cryptic species of Chiasmocleis from the Atlantic Forest of Brazil are described. Two of these species occur in the northeastern states of Sergipe and Bahia, whereas the third species is found in the southeastern state of São Paulo. The new species can be distinguished from other congeneric species by the molecular data, as evidenced in the phylogeny, and by a combination of morphological characters including: size, foot webbing, dermal spines, and coloration patterns. Chiasmocleis species differ in osteological traits, therefore we also provide an osteological description of each new species and comparsions with data reported for other species in the genus