NonParRolCor: An R package for estimating rolling correlation for two regular time series

The R package NonParRolCor estimates rolling window correlations between two regular time series. The statistical significance estimated for the rolling correlation coefficients addresses effects due to multiple testing. This is done via Monte Carlo simulations by permuting one of the variables and keeping the other fixed. NonParRolCor uses parallel computing to improve computation time when statistical significance is estimated. NonParRolCor contains four functions for estimating and plotting the correlation coefficients for a single window-length or a band of window-lengths. NonParRolCor's functions are highly flexible, since they contain several parameters for controlling the estimation of correlation and the plot output. Some applications are presented to illustrate its use. © 2023 The Author(s)JMPM acknowledges to the Excellence Unit GECOS, Spain (reference number CLU-2019-03 ) at the Universidad de Salamanca for funding support. We would like to show our gratitude to the anonymous reviewers and the Editor Prof. Sobie whose comments and suggestions have been very helpful in improving this paper

Choice of Metrics used in Collaborative Filtering and their Impact on Recommender Systems

The capacity of recommender systems to make correct predictions is essentially determined by the quality and suitability of the collaborative filtering that implements them. The common memory-based metrics are Pearson correlation and cosine, however, their use is not always the most appropriate or sufficiently justified. In this paper, we analyze these two metrics together with the less common mean squared difference (MSD) to discover their advantages and drawbacks in very important aspects such as the impact when introducing different values of k-neighborhoods, minimization of the MAE error, capacity to carry out a sufficient number of predictions, percentage of correct and incorrect predictions and behavior when attempting to recommend the n-best items. The paper lists the results and practical conclusions that have been obtained after carrying out a comparative study of the metrics based on 135 experiments on the MovieLens database of 100,000 ratios

El día "uno" de la Creación. Interpretación del Gen 1,1-5 según Filón de Alejandría

Los primeros versículos del Génesis, por su contenido tanto respecto a la Creación como a la Trinidad, fueron un lugar de interés para los escritores cristianos primitivos y para el nacimiento de la Teología. Por un lado, las primeras palabras reveladas brindan argumentos a la cosmovisión cristiana en la doctrina sobre el Dios Creador y Providente y sobre la dependencia que el mundo tiene de sus manos, frente a filosofías contemporáneas negadoras de la creación o fatalista

Study using microsatellites of main varieties of iberian pig

It is characterized a sample of 10 Iberian Pigs strains and one of Duroc with a panel of 25 microsatellites. It was detected a number of alleles between 4 and 20. The values of Heterocigosity by locus ranged between 0.03 for S0355 and 0.73 for S0068. The mean of q as genetic diversity measure was 0.12. After UPGMA tree representation from standard genetic distances, the strains Lampiño, Torbiscal were very well defined but Retinto Extremeño, Entrepelado and Silvela were not.Se caracteriza una muestra de 10 variedades de Cerdo Ibérico y una de Duroc con un panel de 25 microsatélites. Se detectó un número de alelos entre 4 y 20. Los valores de heterocigosidad por locus fluctuaron entre 0,03 para S0355 y 0,73 para S0068. La media del valor de q como medida de la diversidad genética fue de 0,12. Después de la representación de la distancia genética estándar usando el UPGMA algoritmo, las variedades Lampiño y Torbiscal se encontraron muy bien definidas, pero en el caso de las variedades Retinto extremeño, Entrepelado y Silvela no fue así

La utilización del ordenador en la realización de experiencias de laboratorio

In this work we expose the principles and teaching impact of the applications of the computer means to carry out the real experiments in the teaching laboratory