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Copyright of FACSalud is the property of Revista FACSalud and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Research based in number theory, have found that the distribution of prime numbers can be analyzed by a power law, and the distances between consecutive prime numbers from multifractal features. Considering the above, it was seek to determine the statistical fractal dimension of the frequency distribution of the distances between consecutive prime numbers, calculated within the five million natural numbers. For this, the distance between consecutive prime numbers was calculated, which are within the five million natural numbers. The distribution of frequencies of the distances between prime numbers was organized, to evaluate if it had a hyperbolic behavior, to subsequently apply the Zipf-Mandelbrot law, and find the statistical fractal dimension of this distribution. It was found that the distribution of frequencies of the distances between consecutive prime numbers varied between 1 and 32463, the correlation coefficient R2 was 0.8017 and the fractal dimension 0.2973. In this way, the degree of complexity of the frequency of appearance of consecutive distances established from the statistical fractal dimension opens the possibility of finding mathematical orders in the way that prime numbers are distributed. [ABSTRACT FROM AUTHOR]

Copyright of Apuntes Universitarios: Revista de Investigación is the property of Universidad Peruana Union Filiar Tarapoto and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mendive - Revista de Educacion is the property of Universidad de Pinar del Rio and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction--Internal control, as the backbone of the organizational system, has gained popularity due to its importance and relationship with the rest of the processes, evidencing its transversal nature. Objective--Design a procedure for the integrated management of Internal Control, with a multi-criteria approach that identifies the weaknesses of this system, to manage and improve its effectiveness. Methodology--Theoretical and empirical methods such as historical-logical analysis, the analytical-synthetic method, the inductive-deductive method, as a way to analyze the prevailing trends and the systemic approach during the research process. Empirical methods include individual interviews, surveys, checklists, observation and analysis of documents. Statistical methods such as descriptive statistics and mathematical methods such as --Saaty, AHP of Saaty, Scoring, diffuse compensatory logic, entropy method, Petri nets and Decision Theory in general were used. Results--From the conception of a theoretical model, materialized in a general procedure subject to mathematical models with a multi-criteria approach, which allows managing, in an integrated manner, the Internal Control system in Cuban organizations. This system is integrated with management control tools, highlighting the balanced scorecard and process management. The proposed multi-attribute mathematical model allows the implementation and evaluation of the components and rules of Internal Control and materialize it in the processes of the organization, by identifying the failures that affect the satisfaction of society. The design with a multi-criteria approach to the balanced scorecard for Internal Control allows the results to be measured systemically and integrating the four perspectives with the five components. Conclusions--The general procedure designed, with three phases, constitutes a guide to develop the Internal Control management system with a process, systemic, multi-criteria and strategic approach, helping to raise the level of implementation of this system, in the same way It forms the level of integration with the processes, maturity, the effectiveness of its management and the improvement of this process. In addition, it is valid prospectively complying with the principles and characteristics. In addition to the formation of a strategic map with direct and indirect relationships through fuzzy logic without contradicting the objective of organizations with or without profit. [ABSTRACT FROM AUTHOR]

The research exposes the main results obtained in the classification of innovation capabilities in the Center for Apicultural Research (CIAPI). Techniques of mathematical statistics, documentary analysis, interviews, surveys, and Delphi method by round are applied. Expert opinion is validated with the application of the Kendall W coefficient and its non-parametric hypothesis test. The entity has identified its key technologies for the achievement of innovation, personnel and possesses the necessary knowledge for their use. The proposed classification table is designed to evaluate innovation capabilities, which shows that although the CIAPI does not present the characteristics of a totally innovative entity, it can potentially become one with trained personnel involved in the requirements of an innovation model. [ABSTRACT FROM AUTHOR]

Introduction: the universities should respond to the demands of the society, the teaching-learning process of their subjects should be to tone with the current technological development and, for it, to adapt the teaching to the learning style of their students, marked by their individual differences. Objective: to value the necessity to assist the individual differences of the students in the teaching-learning process from the current perspective of technological development. Methods: through a descriptive study from September 2019 to July 2020 in the Faculty of Technology-Nursing in the Medical Sciences University from Villa Clara, a theoretical methods: historical-logical and analytical-synthetic, empirical: documentary analysis and survey and mathematical: descriptive statistics were applied to a population-sample composed of all first year students of Short Cycle Higher Education. Results: the program analysis of the subject Introduction to Research Methodology allowed to verify its possibilities of being fulfilled taking into account the individual differences of the students according to the current technological development, and the questionnaire showed their necessity to have more up-to-date technology lessons, which they can apply in their study activity with satisfactory academic results. Conclusions: it is important to accomplish the organization and successful management of the teaching-learning process by the professor in order to obtain a better academic results for the students, the use of technologies is fundamental in the change and transformation of current university teaching and technological development demands professionals who are prepared to be part of it. [ABSTRACT FROM AUTHOR]

Copyright of Apuntes Universitarios: Revista de Investigación is the property of Universidad Peruana Union Filiar Tarapoto and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mendive - Revista de Educacion is the property of Universidad de Pinar del Rio and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Matronas Profesion is the property of Ediciones Mayo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses probabilistic number theory and approaches it from a more restricted point of view that will allow to concentrate on some specific aspects with probabilistic number theory as the study of the asymptotic behavior of sequences of arithmetically defined random variables. It further presents several reference covering a wide variety of recent interactions between number theory and probability.

Copyright of Revista Mexicana de Endocrinología, Metabolismo y Nutrición is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study considers the flexible flowshop scheduling problem with anticipatory sequence dependent setup times and minimization of total tardiness. An ant colony optimization ACS (ant colony system) algorithm is proposed, hybridized with a pairwise interchange neighborhood search, which is evaluated on a set of test problems generated in previous studies, and compared with other solving methods. The proposed algorithm shows better results than those obtained by any other methods. [ABSTRACT FROM AUTHOR]

The premium of the sum of two risks X and Y with positive dependence PQD and NQD negative dependence and its impact is studied in this paper using copulas as the general structure that governs such dependence. We propose a demonstration of Hoeffding's lemma and is used to calculate the variance of X + Y. Various premium principles (variance, standard deviation, variance as amended) and most commonly used measures of dependence (τ of Kendall, dependence on the tail) are propoused and used. Several numerical examples risks of dependence with some Archimedean copulas are presented. [ABSTRACT FROM AUTHOR]

Copyright of Avances en Enfermería is the property of Editorial Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To be able to resolve tomographic inversion problems in travel time, it is necessary the construction of distance matrices containing information of survey array geometry, the discretized domain shape and the distance traveled by rays in each area elements that compose it. Domain considered are generally rectangular for ease of geometric resolution. In this work is circular due to the need to carry out investigation in columns of this shape. Distance matrices are used to solve the linear system, which leads to the determination of velocity values in each element of the domain. Taking in mind discretization, there are several possibilities for the construction of arrays of pixels: may those be defined in one quadrant and obtaining the rest by symmetry; build arrays using any size pixels independent of the quadrant, and finally construct distance matrices with square pixels. Each option will provide access to new research possibilities. In this work an original procedure was developed for the construction of matrices with elements of the last type. The procedure was validated with simulated data using the damped least squares solution (DLSS) method, which demonstrated the efficiency of the algorithm. [ABSTRACT FROM AUTHOR]

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article has as the main objective: to analyze some components of statistic culture and how to made the approach didactically from the educational process of the curriculum, which is the result of the research develop by the author and has been tested on the pedagogical practice during the years of experience of him as professor of this discipline; making possible from the research's scientific foundations bases obtain a better understanding of this important aspect to society. [ABSTRACT FROM AUTHOR]

Copyright of Gerencia Tecnologica Informatica is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Six-Sigma is a strategy for continuous quality improvement based on facts and data that attempts to reach higher quality standards and lower number of defects. Six-Sigma provides a structured, analytic and rational approach that allows the implementation of quality improvement projects according to the planned objectives. Although its current popularity is mainly due to its widespread implementation in the industrial sector, it is also being increasingly used in the services sector, such as in health care services, where the customer's satisfaction has an even more crucial relevance. Six-Sigma involves the use of a wide range of statistical tools; in fact, the term sigma means standard deviation, which is a key measure of the distribution's variability. In this paper the statistical tools more suitable for each phase of Six-Sigma's adoption are presented as well a proposal of its adoption in health care services. [ABSTRACT FROM AUTHOR]

The study of variability in categorical characteristics is rarely discussed. From a less used viewpoint of variability in quantitative variables, as it is the one of dissimilarity, which is different from the dispersion that, for example, the variance provides, we propose the construction of two coefficients that measure the variability in qualitative or categorical variables, which we call coefficients of dissimilarity. Simple examples are provided to introduce the measures, so that the teacher can also evaluate the idea students have about variability, dispersion and dissimilarity. [ABSTRACT FROM AUTHOR]

In this work we have collected estimators of the population proportion through the use of auxiliary information under simple random sampling. We analyzed the main properties of these estimators. Theorethical properties suggest that the estimators with use of auxiliary information can outperform alternative methods, and the results derived from a Monte Carlo simulation study support this view. Has made an application on a population of Risk of Acidication in Lakes in the Northeastern states of the U.S. conducted by the Environmental Monitoring and Assessment Program of the US Environmental Protection Agency. In the application we have compared the different estimators each other with the standard stimators. [ABSTRACT FROM AUTHOR]

In the paper the results of the combined strategy formed by Robust Principal Component Analysis and CUR matrix decomposition are applied to a practical problem for adjusting a regression model by using Partial Least Squares (PLS). The conclusions concerning their advantages of such an approach as well information about the adjusted models are given. [ABSTRACT FROM AUTHOR]

Background: The elaboration of growth and development curves applicable to children of a community is an excellent tool to ensure adequate monitoring of growth. Materials Methods: Cross sectional study with 640 normal children monitored in consultation between 2005 and 2010 in ASSBASALUD ESE (Manizales, Colombia). Measurements of weight, height, and head circumference were taken from their stories at birth, at 24, 48 and 60 months. Based on these data the parameters of the distributions by gender for weight, length and head circumference for each age were found. Additionally, for each case were found percentiles. Results: The parameters for each distribution of weight, length and head circumference for boys and girls at birth and at 24, 48, and 60 months were presented. Growth curves are presented for weight in children. Comparisons are made with 4 studies: the World Health Organization, the CDC (Centers of diseases Control), and two Spanish studies. Conclusions: Although these growth curves can not be generalized to the entire Colombian population, due to the limited representativeness of the sample relative to the population of the nation, it can be inferred that international studies are not mentioned fully applicable to the population served in ASSBASALUD ESE, and it is urgent to undertake studies on this issue in local, regional, and national levels. [ABSTRACT FROM AUTHOR]

Copyright of Analítika: Journal of Statistical Analysis / Revista de Análisis Estadístico is the property of Analitika: Journal of Statistical Analysis / Revista de Analisis Estadistico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this communication, a critical bibliographical survey on discrete least squares (LS) presentation is firstly made, and especially of data fitting (DF). Afterwards, to help to overcome part of the limitations and deficiencies that were shown in the bibliography, a formal presentation of generalized least squares (GLS, in general non linear by default) is made, and very especially of DF for vector valued functions (VVF); the corresponding non linear system of equations, extension of the well known normal equations, is derived. From there, some particular cases are obtained, for example, when the function is real valued, and when the approximation is linear. This second example is just linear generalized least squares (LGLS). [ABSTRACT FROM AUTHOR]

The technique of Randomized Response has been introduced to reduce the risk of evasive answer or no-response in survey samplings of sensitive issues to estimate the total of individuals with that sensitive characteristic. We also know that highly efficient strategies of estimation require strong auxiliary information. Hence, in this article we obtain and compare two estimators: The Rao-Hartley-Cochran (RHC) estimator with Warner's model and the RHC estimator with Greenberg's model, both in a finite population setting. We will show via simulation that ŧA1,RHC,π the RHC π-estimator in Warner's model is less efficient than ŧA1,RHC,π, the RHC π-estimator in Greenberg's model. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nested model selection for longitudinal data using information criteria and the conditional adjustment strategy. Knowledge of the subject matter plays a vital role when attempting to choose the best possible linear mixed model to analyze longitudinal data. To date, in the absence of strong theory, much of the work has focused on modeling the covariance matrix by comparing non-nested models using selection criteria. In this paper, we compare the performance of conditional likelihood ratio test (LRT) and several versions of information criteria for selecting nested mean structures and/or nested covariance structures, assuming that the true data-generating processes are known. Simulation results indicate that the efficient criteria performed better than their consistent counterparts when covariance structures used in the data generation were complex, and worse when structures were simple. The conditional LRT under full maximum likelihood (FML) estimation was better overall than the other criteria in terms of selection performance. However, under restricted maximum likelihood (REML), estimation was inferior. We also find that the strategy suggested in the statistical literature of using REML for covariance structure selection, and FML for mean structure selection may be misleading. [ABSTRACT FROM AUTHOR]

The resplendent Quetzal (Pharomachrus mocinno) is an endemic Mesoamerican bird species of conservation concern. Within this species, the subspecies P. m. costaricensis and P. m. mocinno, have been recognized by apparent morphometric differences; however, presently there is no sufficient data for confirmation. We analyzed eight morphometric attributes of the body from 41 quetzals: body length, tarsus and cord wing, as well as the length, wide and depth of the bill, body weight; and in the case of the males, the length of the long upper-tail cover feathers. We used multivariate analyses to discriminate morphometric differences between subspecies and contrasted each morphometric attribute between and within subspecies with paired non-parametric Wilcoxon test. In order to review the intraspecific taxonomic status of this bird, we added phylogenetic analysis, and genetic divergence and differentiation based on nucleotide variations in four sequences of mtDNA. The nucleotide variation was estimated in control region, subunit NDH6, and tRNAGlu and tRNAPhe in 26 quetzals from eight localities distributed in five countries. We estimated the genetic divergence and differentiation between subspecies according to a mutation-drift equilibrium model. We obtained the best mutation nucleotide model following the procedure implemented in model test program. We constructed the phylogenetic relationships between subspecies by maximum parsimony and maximum likelihood using PAUP, as well as with Bayesian statistics. The multivariate analyses showed two different morphometric groups, and individuals clustered according to the subspecies that they belong. The paired comparisons between subspecies showed strong differences in most of the attributes analyzed. Along the four mtDNA sequences, we identified 32 nucleotide positions that have a particular nucleotide according to the quetzals subspecies. The genetic divergence and the differentiation was strong and markedly showed two groups within P. mocinno that corresponded to the quetzals subspecies. The model selected for our data was TVM+G. The three phylogenetic methods here used recovered two clear monophyletic clades corresponding to each subspecies, and evidenced a significant and true partition of P. mocinno species into two different genetic, morphometric and ecologic groups. Additionally, according to our calculations, the gene flow between subspecies is interrupted at least from three million years ago. Thus we propose that P. mocinno be divided in two independent species: P. mocinno (Northern species, from Mexico to Nicaragua) and in P. costaricensis (Southern species, Costa Rica and Panama). This new taxonomic classification of the quetzal subspecies allows us to get well conservation achievements because the evaluation about the kind and magnitude of the threats could be more precise. [ABSTRACT FROM AUTHOR]

Time series prediction is an important research problem due to its implications in engineering, economics, finance and social sciences. An important topic about this problematic is the development of new models and its comparison with previous approaches in terms of forecast accuracy. Recently, support vector machines (SVM) have been used for time series prediction, but the reported experiences are limited and there are some problems related to its specification. The aim of this paper is to propose a novel technique for estimating some constants of the SVM usually fixed empirically by the modeler. The proposed technique is used to estimate several SVM with the aim of forecast five benchmark time series; the obtained results are compared with the statistics reported in other papers. The proposed method allow us to obtain competitive SVM for the time series forecasted in comparison with the results obtained using other most traditional models. [ABSTRACT FROM AUTHOR]

This study examines the possible influence of a reader's place of origin on the comprehension of health communication messages and on the formation of attitudes and intentions to behave in a precautionary manner. A measurement instrument with a reading comprehension, attitude and intention scale was administered to a group of individuals of Puerto Rican and Dominican origin (N=40) living in San Juan, Puerto Rico. The reading comprehension scale used two texts with different levels of difficulty (relatively easy and middle) in accordance with the Readability Formula for Spanish of Francisco Szigriszt Pazos. Statistical analyses revealed that no statistically significant differences (p>.05) were found in the arithmetic means of the correct answers when the two levels of difficulty were compared among the participants. There was no statistically significant difference (p>.05) among the sample for the relatively easy level of the reading test; however, for the middle level, there was a statistically significant difference (p<.05). Regression analyses run showed that comprehension and attitude together do not significantly predict the degree of intention to adopt healthy preventive behavior. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently leak detection (LD) in water pipelines is an active area of research that is attracting increasing interest due to the importance of the safe transport of this vital resource. This work considers the problem of LD in water pipes by means of analytical redundancy, based on a mathematical model and using state estimation techniques. The main aim of this work is to research, propose, implement and apply efficient algorithms that allow to tackle generally the LD. To achieve this, a bank of filters including Kalman Filters (KF) and Particle Filter (PF) is proposed and evaluated. Thus a conceptual contribution to the formulation of the LD problem is proposed in a modular way so that future studies of other techniques can solve the problem. In addition, efficient and reliable algorithms are developed, based on a state estimator capable of responding to industrial standards such as the delivery, from input and output measures available, of a reliable estimate of the state of the process and that is independent of the linear or non-linear dynamics and easy to handle and configure. The computer simulation and the experimental results show the effectiveness of combining KF with PF for the simple case of two sequential leaks in a pipe, presenting advantages such as rapid convergence and reducing the estimation error which are important factors in LD in water pipeline. [ABSTRACT FROM AUTHOR]

Copyright of Archivos de Medicina Veterinaria is the property of Universidad Austral de Chile, Facultad de Ciencias Veterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estudios Gerenciales is the property of Universidad ICESI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)