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Javier E. Contreras-Reyes

Bio: Javier E. Contreras-Reyes is an academic researcher from Valparaiso University. The author has contributed to research in topics: Multivariate statistics & Skewness. The author has an hindex of 15, co-authored 51 publications receiving 583 citations. Previous affiliations of Javier E. Contreras-Reyes include Pontifical Catholic University of Chile & University of the Bío Bío.

Papers published on a yearly basis

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Journal ArticleDOI
TL;DR: In this paper, the authors extend the mutual information index to the full symmetric class of multivariate elliptical distributions and then to the more flexible families of multiivariate skew-elliptical distributions.
Abstract: . The entropy and mutual information index are important concepts developed by Shannon in the context of information theory. They have been widely studied in the case of the multivariate normal distribution. We first extend these tools to the full symmetric class of multivariate elliptical distributions and then to the more flexible families of multivariate skew-elliptical distributions. We study in detail the cases of the multivariate skew-normal and skew-t distributions. We implement our findings to the application of the optimal design of an ozone monitoring station network in Santiago de Chile.

81 citations

Journal ArticleDOI
04 Sep 2012-Entropy
TL;DR: The aim of this work is to provide the tools to compute the well-known Kullback–Leibler divergence measure for the flexible family of multivariate skew-normal distributions, and uses the Jeffreys divergence measure to compare the multivariate normal distribution with the skew-multivariatenormal distribution.
Abstract: The aim of this work is to provide the tools to compute the well-known Kullback–Leibler divergence measure for the flexible family of multivariate skew-normal distributions. In particular, we use the Jeffreys divergence measure to compare the multivariate normal distribution with the skew-multivariate normal distribution, showing that this is equivalent to comparing univariate versions of these distributions. Finally, we applied our results on a seismological catalogue data set related to the 2010 Maule earthquake. Specifically, we compare the distributions of the local magnitudes of the regions formed by the aftershocks.

76 citations

Journal ArticleDOI
TL;DR: In the package afmtools for R, a number of statistical tools for analyzing ARFIMA models are implemented, which contains functions for parameter estimation, exact autocovariance calculation, predictive ability testing and impulse response function computation, among others.
Abstract: The autoregressive fractionally integrated moving average (ARFIMA) processes are one of the best-known classes of long-memory models. In the package afmtools for R, we have implemented a number of statistical tools for analyzing ARFIMA models. In particular, this package contains functions for parameter estimation, exact autocovariance calculation, predictive ability testing and impulse response function computation, among others. Furthermore, the implemented methods are illustrated with applications to real-life time series.

40 citations

Journal ArticleDOI
TL;DR: This paper analyzes the CF time series via skew-gaussian distributions that consider the asymmetry produced by extreme events and uses the Jensen–Shannon distance to compare CF by length classes, finding that for high values of shape parameter, JS distance tends to be more sensible to detect discrepancies than Jeffrey's divergence.
Abstract: Biological-fishery indicators have been widely studied. As such the condition factor (CF) index, which interprets the fatness level of a certain species based on length and weight, has been investigated, too. However, CF has been studied without considering its temporal features and distribution. In this paper, we analyze the CF time series via skew-gaussian distributions that consider the asymmetry produced by extreme events. This index is characterized by a threshold autoregressive model and corresponds to a stationary process depending on the shape parameter of the skew-gaussian distribution. Then we use the Jensen–Shannon (JS) distance to compare CF by length classes. This distance has mathematical advantages over other divergences such as Kullback–Leibler and Jeffrey’s, and the triangular inequality property. Our results are applied to a biological catalogue of anchovy (Engraulis ringens) from the northern coast of Chile, for the period 1990–2010 that consider monthly CF time series by length classes and sex. We find that for high values of shape parameter, JS distance tends to be more sensible to detect discrepancies than Jeffrey’s divergence. In addition, the body condition of male anchovies with higher lengths coincides with the ending of the moderate-strong El Nino event 91–92 and for both males and females, the smaller lengths coincide with the beginning of the strong El Nino event 97–98.

37 citations

Journal ArticleDOI
TL;DR: A non-linear regression model in which the error distribution allows for heteroskedasticity and belongs to the skew-normal (SMSN) distributions family of scale mixtures, thus eliminating the need to transform the dependent variable using techniques such as the Box–Cox transformation.

35 citations


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01 Jan 2016
TL;DR: The table of integrals series and products is universally compatible with any devices to read and is available in the book collection an online access to it is set as public so you can get it instantly.
Abstract: Thank you very much for downloading table of integrals series and products. Maybe you have knowledge that, people have look hundreds times for their chosen books like this table of integrals series and products, but end up in harmful downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they cope with some harmful virus inside their laptop. table of integrals series and products is available in our book collection an online access to it is set as public so you can get it instantly. Our book servers saves in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the table of integrals series and products is universally compatible with any devices to read.

4,085 citations

Journal ArticleDOI
TL;DR: The scientific books will also be the best reason to choose, especially for the students, teachers, doctors, businessman, and other professions who are fond of reading.
Abstract: In what case do you like reading so much? What about the type of the complex population dynamics a theoretical empirical synthesis book? The needs to read? Well, everybody has their own reason why should read some books. Mostly, it will relate to their necessity to get knowledge from the book and want to read just to get entertainment. Novels, story book, and other entertaining books become so popular this day. Besides, the scientific books will also be the best reason to choose, especially for the students, teachers, doctors, businessman, and other professions who are fond of reading.

627 citations

01 Jan 2016

566 citations