Abstract Statistics is one of the foundations of science, and its teaching in graduate programs has a direct influence on shaping the next generation of researchers. This study provides a general overview of statistics-related courses in stricto sensu graduate programs in Brazil, based on the analysis of the syllabi of 176,823 courses, of which 12,552 contained content related to statistics. Among the findings, it was observed that only a few programs have mandatory courses specifically related to statistics. The higher the concept of the graduate program according to Capes evaluation, the greater the average number of statistics-related courses offered. However, this relationship is not evident in the mandatory courses. Regarding the content of the courses, they can be divided into two main groups: one with a theoretical foundation in probability and statistics, and another focused on applications and the use of tools. There is a small third group of courses offered in the English language. Finally, the availability of courses related to advanced techniques (such as Machine Learning) is much smaller compared to the offering of statistics-related courses, and it is mainly concentrated in Engineering and Exact and Earth Sciences programs.

Resumo A estatística é uma das bases da ciência e seu ensino em programas de pós-graduação tem influência direta na formação da próxima geração de pesquisadores. Este trabalho traz um panorama geral das disciplinas relacionadas à estatística na pós-graduação stricto sensu no Brasil, a partir da análise das ementas das 176.823 disciplinas, sendo 12.552 com conteúdos relacionados à estatística. Dentre os fatos encontrados temos que poucos programas possuem disciplinas obrigatórias relacionadas à estatística. Quanto maior o conceito da pós-graduação na Capes, maior a quantidade média de disciplinas relacionadas à estatística ofertadas. Entretanto, essa relação não está presente nas disciplinas obrigatórias. Com relação ao conteúdo das disciplinas, elas se dividem em dois grandes grupos. Um grupo com base teórica em probabilidade e estatística, outro com foco em aplicações e utilização de ferramentas. Existe um pequeno terceiro grupo de disciplinas, ofertadas na língua inglesa. Por fim, a oferta de disciplinas relacionadas a técnicas avançadas (Machine Learning) é, se comparada à oferta das disciplinas relacionadas à estatística, muito pequena e se concentra, principalmente, nos programas de Engenharia e Ciências Exatas e da Terra.

Abstract Poisson distribution is a popular discrete model used to describe counting information, from which traditional control charts involving count data, such as the c and u charts, have been established in the literature. However, several studies recognize the need for alternative control charts that allow for data overdispersion, which can be encountered in many fields, including ecology, healthcare, industry, and others. The Bell distribution, recently proposed by Castellares et al. (2018), is a particular solution of a multiple Poisson process able to accommodate overdispersed data. It can be used as an alternative to the usual Poisson (which, although not nested in the Bell family, is approached for small values of the Bell distribution) Poisson, negative binomial, and COM-Poisson distributions for modeling count data in several areas. In this paper, we consider the Bell distribution to introduce two new exciting, and useful statistical control charts for counting processes, which are capable of monitoring count data with overdispersion. The performance of the so-called Bell charts, namely Bell-c and Bell-u charts, is evaluated by the average run length in numerical simulation. Some artificial and real data sets are used to illustrate the applicability of the proposed control charts.

Resumo Os avanços nos sistemas de produção buscam sempre alternativas para a melhoraria da produtividade. Uma das práticas recentes adotadas em plantios comerciais de bananas e plátanos referem-se à aplicação de fertilizantes líquidos em cachos, visando ao aumento da produtividade. O objetivo deste trabalho foi verificar se o uso de biofertilizantes à base de vinhaça pura ou associada a outros adubos químicos poderia proporcionar alterações morfofisiológicas nos frutos ou aumento de produtividade no plátano cv Terra Maranhão. Para a execução deste projeto, foi montado, em uma lavoura comercial, um delineamento em blocos casualizados, com 6 tratamentos e 3 repetições, tendo sido avaliadas características de produção e qualidade dos frutos na pós-colheita do plátano cultivar (cv) Terra Maranhão. Como resultado, pôde-se observar que as características morfofisiológicas de frutos recém-colhidos, que impactam a produtividade, como peso dos frutos e dos cachos, foram afetados pelos tratamentos, enquanto características da pós-colheita dos frutos maduros foram pouco afetadas pela aplicação de fertilizantes nos cachos, com exceção do conteúdo de SST. Conclui-se, portanto, com este experimento, que a produtividade da cultura aumentou significativamente em 17%, quando utilizada uma mistura de vinhaça, cloreto de potássio e ureia; entretanto, este mesmo tratamento provocou a redução significativa de 1,3 ºBrix em relação a testemunha.

Abstract Advances in production systems always aim at finding alternatives to improve crop productivity. One of the recent practices adopted in commercial banana and plantain plantations refers to the application of liquid fertilizers in bunches in order to increase productivity. This research aimed at verifying whether the use of biofertilizers based on pure vinasse or associated with other chemical fertilizers would provide morphophysiological changes in fruits or increase the productivity of ‘Terra Maranhão’ plantain cultivars. In order to carry out this project, a randomized block design with 6 treatments and 3 replicates was set up in a commercial crop and the postharvest production and quality characteristics of ‘Terra Maranhão’ plantain fruits were evaluated. The results showed that the morphophysiological characteristics of freshly harvested fruits that impact productivity such as the fruit weight and bunch weight were affected by treatments, as the postharvest characteristics of ripe fruits were little affected by the application of fertilizers in bunches, except for the SST content. It could be concluded that the crop yield increased significantly by 17% when using mixture of vinasse, potassium chloride and urea; however, this treatment caused significant reduction of 1.3 ºBrix compared to control.

ABSTRACT Background: The screening of Trypanosoma cruzi-infected blood donors using two serological techniques frequently leads to conflicting results. This fact prompted us to evaluate the diagnostic performance of four “in-house” immunodiagnostic tests and two commercially available enzyme-linked immunosorbent assays (ELISAs). Material and Methods: One hundred and seventy-nine blood donors, whose screening for Chagas disease was doubtful, underwent three in-house ELISAs, one in-house immunoblotting test (TESA-blot), and two commercial ELISAs (bioMérieux and Wiener) in an attempt to define the presence or absence of infection. Simultaneously, 29 donors with previous positive results from three conventional serological tests and 30 donors with constant negative results were evaluated. Results: The ELISA-Wiener showed the highest rate in sensitivity (98.92%) and the ELISA-bioMérieux, the highest specificity (99.45%), followed by the TESA-blot, which showed superior performance, with lower false-negative (2.18%) and false-positive (1.12%) rates. In series, the combination composed of the TESA-blot and ELISA-bioMérieux showed slightly superior performance, with trifunctional protein deficiency (TFP) = 0.01%. Conclusion: Our study confirms the high sensitivity and specificity of commercial kits. To confirm the presence or absence of T. cruzi infection, the combination of TESA-blot and ELISA-bioMérieux may be suggested as the best alternative. Individually, the TESA-blot performed the closest to the gold standard; however, it is not commercially available.

Resumen En este artículo, discutimos varias propiedades matemáticas y métodos de estimación para una versión reparametrizada de la distribución ponderada de Lindley (RWL). La distribución RWL puede ser particularmente útil para modelar datos de confiabilidad (supervivencia) con función de tasa de riesgo en forma de bañera o creciente. El procedimiento inferencial para obtener las estimaciones de los parámetros se realiza mediante el enfoque de máxima verosimilitud considerando la censura aleatoria a la derecha. Se realizan extensas simulaciones numéricas para investigar y evaluar el rendimiento del método de estimación propuesto. Finalmente, la utilidad del modelo RWL se analiza mediante el uso de dos conjuntos de datos reales.

Abstract In this paper, we discuss several mathematical properties and estimation methods for a reparameterized version of the weighted Lindley (RWL) distribution. The RWL distribution can be particularly useful for modeling reliability (survival) data with bathtub-shaped or increasing hazard rate function. The inferential procedure to obtain the parameter estimates is conducted via the maximum likelihood approach considering random right-censoring. Extensive numerical simulations are carried out to investigate and evaluate the performance of the proposed estimation method. Finally, the potentiality of the RWL model is analyzed by employing two real data sets.

Abstract The gamma distribution has been extensively used in many areas of applications. In this paper, considering a Bayesian analysis we provide necessary and sufficient conditions to check whether or not improper priors lead to proper posterior distributions. Further, we also discuss sufficient conditions to verify if the obtained posterior moments are finite. An interesting aspect of our findings are that one can check if the posterior is proper or improper and also if its posterior moments are finite by looking directly in the behavior of the proposed improper prior. To illustrate our proposed methodology these results are applied in different objective priors.

RESUMO OBJETIVO Avaliar duas evidências de validade da escala de qualidade da dieta (ESQUADA) para seleção dos itens com melhor discriminação da qualidade da dieta dos brasileiros e propor uma descrição em níveis de escore. MÉTODOS Adolescentes e adultos brasileiros e residentes no país (n = 2.059), responderam a um questionário on-line com 52 itens, compartilhado em redes sociais e listas de correio eletrônico entre março e abril de 2018. Foram aplicados testes estatísticos para análise de evidências de validade e confiabilidade do instrumento. A análise fatorial foi aplicada para estudo da dimensionalidade dos itens do questionário. A teoria de resposta ao item foi aplicada para identificar a discriminação e localização dos itens no continuum , construir a escala e avaliar o comportamento diferencial dos itens quanto ao sexo e idade. RESULTADOS Dentre os 52 itens do questionário, 25 apresentaram maior precisão de medida, com ajuste e confiabilidade adequados. O item sobre o costume de comer alimentos ultraprocessados em casa apresentou a melhor discriminação da qualidade da dieta. Nenhum item apresentou comportamento diferencial quanto a sexo e idade. Na construção da ESQUADA foram identificados cinco níveis de qualidade da dieta: “muito ruim”, “ruim”, “boa”, “muito boa” e “excelente”. Observou-se que enquanto cereais matinais e/ou barrinhas de cereais são consumidos com maior frequência por indivíduos com qualidade da dieta “muito ruim”; castanhas e/ou nozes são consumidos mais frequentemente por aqueles indivíduos com qualidade da dieta “excelente”. CONCLUSÕES A ESQUADA é composta por 25 itens precisos e sem comportamento diferencial para avaliar a qualidade da dieta dos brasileiros. A construção da ESQUADA possibilitou reconhecer consumo e práticas alimentares característicos de cada nível de qualidade da dieta.

ABSTRACT OBJECTIVE Assess two validity evidences of the diet quality scale (ESQUADA) for the selection of items with better discrimination of the Brazilians’ diet quality and propose a description in score levels. METHODS Brazilian adolescents and adults residing in the country (n = 2,059) answered an online questionnaire with 52 items, shared on social networks and email lists between March and April 2018. Statistical tests were applied to analyze the validity and reliability of the instrument’s evidence. Factor analysis was applied to study the dimensionality of the questionnaire items. Item response theory was applied to identify the discrimination and location of items on the continuum, construct the scale and assess the differential item functioning in terms of sex and age. RESULTS Among the 52 items of the questionnaire, 25 had greater measurement accuracy, with adequate adjustment and reliability. The item on the habit of eating ultra-processed foods at home showed the best discrimination of diet quality. No item showed differential functioning regarding sex and age. In the construction of the ESQUADA, five diet quality levels were identified: very poor, poor, good, very good and excellent. It was observed that while breakfast cereals and/or cereal bars are more frequently consumed by individuals with “very poor” diet quality; nuts and/or walnuts are most often consumed by those individuals with “excellent” diet quality. CONCLUSION The ESQUADA consists of 25 precise items with no differential functioning to assess the quality of Brazilians’ diet. The construction of the ESQUADA made it possible to recognize food consumption and dietary practices characteristic of each level of diet quality.

ABSTRACT OBJECTIVE Assess two validity evidences of the diet quality scale (ESQUADA) for the selection of items with better discrimination of the Brazilians’ diet quality and propose a description in score levels. METHODS Brazilian adolescents and adults residing in the country (n = 2,059) answered an online questionnaire with 52 items, shared on social networks and email lists between March and April 2018. Statistical tests were applied to analyze the validity and reliability of the instrument’s evidence. Factor analysis was applied to study the dimensionality of the questionnaire items. Item response theory was applied to identify the discrimination and location of items on the continuum, construct the scale and assess the differential item functioning in terms of sex and age. RESULTS Among the 52 items of the questionnaire, 25 had greater measurement accuracy, with adequate adjustment and reliability. The item on the habit of eating ultra-processed foods at home showed the best discrimination of diet quality. No item showed differential functioning regarding sex and age. In the construction of the ESQUADA, five diet quality levels were identified: very poor, poor, good, very good and excellent. It was observed that while breakfast cereals and/or cereal bars are more frequently consumed by individuals with “very poor” diet quality; nuts and/or walnuts are most often consumed by those individuals with “excellent” diet quality. CONCLUSION The ESQUADA consists of 25 precise items with no differential functioning to assess the quality of Brazilians’ diet. The construction of the ESQUADA made it possible to recognize food consumption and dietary practices characteristic of each level of diet quality.

RESUMO OBJETIVO Avaliar duas evidências de validade da escala de qualidade da dieta (ESQUADA) para seleção dos itens com melhor discriminação da qualidade da dieta dos brasileiros e propor uma descrição em níveis de escore. MÉTODOS Adolescentes e adultos brasileiros e residentes no país (n = 2.059), responderam a um questionário on-line com 52 itens, compartilhado em redes sociais e listas de correio eletrônico entre março e abril de 2018. Foram aplicados testes estatísticos para análise de evidências de validade e confiabilidade do instrumento. A análise fatorial foi aplicada para estudo da dimensionalidade dos itens do questionário. A teoria de resposta ao item foi aplicada para identificar a discriminação e localização dos itens no continuum , construir a escala e avaliar o comportamento diferencial dos itens quanto ao sexo e idade. RESULTADOS Dentre os 52 itens do questionário, 25 apresentaram maior precisão de medida, com ajuste e confiabilidade adequados. O item sobre o costume de comer alimentos ultraprocessados em casa apresentou a melhor discriminação da qualidade da dieta. Nenhum item apresentou comportamento diferencial quanto a sexo e idade. Na construção da ESQUADA foram identificados cinco níveis de qualidade da dieta: “muito ruim”, “ruim”, “boa”, “muito boa” e “excelente”. Observou-se que enquanto cereais matinais e/ou barrinhas de cereais são consumidos com maior frequência por indivíduos com qualidade da dieta “muito ruim”; castanhas e/ou nozes são consumidos mais frequentemente por aqueles indivíduos com qualidade da dieta “excelente”. CONCLUSÕES A ESQUADA é composta por 25 itens precisos e sem comportamento diferencial para avaliar a qualidade da dieta dos brasileiros. A construção da ESQUADA possibilitou reconhecer consumo e práticas alimentares característicos de cada nível de qualidade da dieta.

Resumo: O presente estudo teve como objetivo analisar os fatores associados às falhas dos equipamentos da colheitadeira de cana-de-açúcar, cujas máquinas têm grande importância no processo de colheita e nos custos envolvidos. Parte dos dados foi originalmente fornecida por uma empresa localizada no interior de São Paulo, de duas máquinas, coletadas de janeiro de 2015 a agosto de 2017, correspondendo a 2,5 culturas. O conjunto geral de dados foi obtido de três fontes diferentes: um sistema de rastreamento de parada, que fornece o rastreamento de um histórico de manutenção preventiva e corretiva do equipamento analisado; dados de telemetria do equipamento, capturados através de sistemas de computador embarcados, instalados no tipo de máquina em estudo, que fornecem informações sobre sua operação; e dados meteorológicos do Instituto Nacional de Meteorologia do Brasil. Análises multivariadas foram usadas, como componentes principais e modelos de regressão múltipla, criando, assim, um modelo de previsão considerando a próxima interrupção do equipamento e apontando as causas de falhas no processo. Assim, os resultados apontam para algumas melhorias relacionadas ao esquema de confiabilidade individualizado, a fim de reduzir o número de paradas corretivas dadas ao equipamento.

Abstract: The present study aimed to analyze factors associated with the equipment failures of the sugarcane harvester, whose machineries has high importance in the harvest process and cost involved. Part of the data was originally provided by a company located in the countryside of Sao Paulo State, from two machines, collected from January 2015 to August 2017, corresponding to 2.5 crops. The overall dataset was obtained from three different sources: a stop-tracking system, which provides the track of a preventive and corrective maintenance historical of the analyzed equipment; telemetry data of the equipment, captured through embedded computer systems, installed in the machine’ type under study, which provide information on its operation; and meteorological data from the Brazilian National Institute of Meteorology. Multivariate analyzes were used such as principal components and multiple regression models, therefore creating a model for prediction considering the next equipment’ break, then pointing to causes of process failures. Thus, the results point to some improvements concerned with individualized reliability scheme in order to reduce the number of corrective stops given the equipment.

Resumo O presente artigo tem como objetivo fornecer subsídios para que pesquisadores em terapia ocupacional possam realizar procedimentos de estatística básica de maneira mais flexível e independente, a partir do sistema R, um software livre e gratuito, cuja popularidade vem aumentando consideravelmente no âmbito acadêmico. Apresentar-se-á, assim, o passo a passo de como instalar e utilizar o programa na realização de leitura e sumarização de dados, bem como no cálculo de estatísticas básicas, nas representações gráficas de dados quantitativos e qualitativos, no cálculo do tamanho amostral e na efetuação de testes de hipóteses e de teste de correlação linear. O banco de dados utilizado nas demonstrações apresentadas é oriundo de uma pesquisa em terapia ocupacional e as análises aqui realizadas resultam de uma demanda compreendida no decorrer de uma disciplina obrigatória do Programa de Pós-Graduação em Terapia Ocupacional da Universidade Federal de São Carlos (UFSCar), por meio da qual foipossívellevantarosprincipaisprocedimentosestatísticosutilizadospelospesquisadoresemsuaspesquisas.

Abstract In this paper, it is presented a simple guide for researchers in occupational therapy to perform basic statistical analysis in a flexible and independent way, using the R software, that is a free open source software which its popularity has been increased considerably in many fields. We have presented a step-by-step guide about how to install such software, it is also discussed the necessary steps to include the data set and perform basic statistical analysis, such as the calculation of sample size, basic statistics, graphical presentation, hypothesis tests, and the linear correlation test. The dataset considered in this study comes from a research in occupational therapy and the topics considered are result of the common statistical procedures that were face in the course of the Post Graduation Program in Occupational Therapy at the Federal University of São Carlos (UFSCar), in which were possible to find the principal statistical procedures used by the researchers in applications.

ABSTRACT In this paper, a new software for Statistical Process Control (SPC) is proposed. The system, the so-called CEP Online, was developed based on statistical computing resources of well-known free softwares, such as HTML, PHP, R and MySQL under an online server with operating system Linux Ubuntu. The main uni and multivariate SPC tools are available for monitoring and evaluation of manufacturing and non-manufacturing production processes over time. Some advantages of the new software are: (i) low operational cost, since it is cloud-based, only needing a computer connected to the Internet; (ii) easy to use with great interaction with the user; (iii) it does not require investment in any specific hardware or software; (iv) real time reports generation on process condition monitoring and process capability. Thus, the CEP Online offers for SPC practitioners fast, efficient and accurate SPC procedures. Therefore, CEP Online becomes an important resource for those who have no access to non-free softwares, such as SAS, SPSS, Minitab and STATISTICA. To the best of our knowledge, the CEP Online is unique with respect to its characteristics.

Abstract: In this paper, we revisit the Wilson-Hilferty distribution and presented its mathematical properties such as the r-th moments and reliability properties. The parameters estimators are discussed using objective reference Bayesian analysis for both complete and censored data where the resulting marginal posterior intervals have accurate frequentist coverage. A simulation study is presented to compare the performance of the proposed estimators with the frequentist approach where it is observed a clear advantage for the Bayesian method. Finally, the proposed methodology is illustrated on three real datasets.

ABSTRACT In this paper we present the development of a modulated web based statistical system, hereafter MWStat, which shifts the statistical paradigm of analyzing data into a real time structure. The MWStat system is useful for both online storage data and questionnaires analysis, as well as to provide real time disposal of results from analysis related to several statistical methodologies in a customizable fashion. Overall, it can be seem as a useful technical solution that can be applied to a large range of statistical applications, which needs of a scheme of devolution of real time results, accessible to anyone with internet access. We display here the step-by-step instructions for implementing the system. The structure is accessible, built with an easily interpretable language and it can be strategically applied to online statistical applications. We rely on the relationship of several free languages, namely, PHP, R, MySQL database and an Apache HTTP server, and on the use of software tools such as phpMyAdmin. We expose three didactical examples of the MWStat system on institutional evaluation, statistical quality control and multivariate analysis. The methodology is also illustrated in a real example on institutional evaluation. A MWStat module was specifically built for providing a real time poll for teacher evaluation at the Federal University of São Carlos (Brazil).

Resumen En este estudio evaluamos la eficiencia de los jugadores de voleibol de acuerdo con su desempeño de ataque, bloqueo y servicio, teniendo en cuenta la estructura composicional de los datos relacionados con los fundamentos de este deporte. Así, consideramos un modelo de regresión de mixtura finita para datos composicionales. La estimación de máxima verosimilitud fue obtenida via un Algoritmo EM. Un estudio de simulación revela que los parámetros son correctamente recuperados. Adicionalmente, los estimadores son asintóticamente insesgados. Considerando dados reales del campeonato de voleyball brasileño nosotros mostramos que el modelo propuesto presenta mejor ajuste que el modelo de regresión usual.

Abstract In this paper, we consider to evaluate the efficiency of volleyball players according to your performance of attack, block and serve, considering the compositional structure of the data related to the fundaments of this sport. In this way, we consider a nite mixture of regression model to compositional data. The maximum likelihood estimation of this model was obtained via an EM algorithm. A simulation study reveals that the parameters are correctly recovery. In addition, the estimators are asymptotically unbiased. By considering real dataset of Brazilian volleyball competition, we show that the model proposed presents best fit than the usual regression model.

Resumo Apocynaceae compõe um grupo de plantas latescentes e está representada por aproximadamente 5.000 espécies em 400 gêneros, com distribuição pantropical. Para o Brasil, estima-se cerca de 77 gêneros e 754 espécies, sendo a Mata Atlântica o domínio de maior diversidade. Para a Mata Atlântica ao norte do Rio São Francisco os trabalhos com foco na família são escassos, limitando-se a listagens florísticas gerais. Desse modo, objetiva-se aqui inventariar e caracterizar morfologicamente as espécies de Apocynaceae nos fragmentos florestais da Usina São José, situada na cidade de Igarassu, Pernambuco. O estudo foi realizado mediante coletas nos fragmentos florestais da área de estudo entre 2015 e 2016, além de consulta a materiais depositados em herbários de referência na região. Foram registradas 17 espécies inseridas em 11 gêneros: Aspidosperma discolor, A. spruceanum, Blepharodon pictum, Ditassa hispida, Hancornia speciosa, Himatanthus bracteatus, Mandevilla hirsuta, M. moricandiana, M. scabra, Matelea ganglinosa, M. orthosioides, Odontadenia lutea, Rauvolfia grandiflora, R. ligustrina, Tabernaemontana flavicans, T. salzmannii e Temnadenia odorifera. São apresentadas chave de identificação, comentários relevantes acerca das espécies e ilustrações.

Abstract Apocynaceae comprises a group of lactescent plants and is represented by approximately 5,000 species and 400 genera, with pantropical distribution. In Brazil, it is estimated about 77 genera and 754 species. The Atlantic Forest harbors the most of species of the family. Floristic studies in the northern region of São Francisco River are still scarce, limited to general floristic checklists. Therefore, the main goal of this study was to produce the taxonomic treatment of the species of Apocynaceae of the forests fragments of Usina São José, in the city of Igarassu, Pernambuco. For this study we conducted field work between 2015 and 2016 and we analyzed vouchers deposited in important herbaria from the Brazilian region of Northeast. We found 17 species and 11 genera: Aspidosperma discolor, A. spruceanum, Blepharodon pictum, Ditassa hispida, Hancornia speciosa, Himatanthus bracteatus, Mandevilla hirsuta, M. moricandiana, M. scabra, Matelea ganglinosa, M. orthosioides, Odontadenia lutea, Rauvolfia grandiflora, R. ligustrina, Tabernaemontana flavicans, T. salzmannii and Temnadenia odorifera. The study follows with identification key, relevant comments about the species and illustrations.