R softwar

En muchas especies es imposible distinguir visualmente los sexos, si bien en algunas de
ellas, machos y hembras muestran pequeñas, pero cuantificables, diferencias  biométricas que pueden usarse para discriminarlos. Este es el caso del grupo de los mosquiteros Phylloscopus, en los que se usa la longitud alar para distinguir los sexos. Hemos desarrollado un método en el que además del ala se tiene en cuenta el tarso y en el que mediante probabilidades multivariantes hemos aumentado la proporción de individuos que se pueden discriminar en tres especies: mosquitero común P. collybita, mosquitero musical P. trochilus y mosquitero ibérico P. ibericus. Además, nuestro método de sexado no tiene sesgos hacia uno de los dos sexos. El objetivo de este artículo es ofrecer una guía práctica para la implementación de nuestro método usando el software libre R.

Urban growth, urban extension, and urban sprawl are sometimes used synonymously, even though they differ conceptually. Urban growth is an increase in the urbanized land cover. One possible means of urban growth is by urban extension. Urban growth according to spontaneous or unplanned urban development is called urban sprawl. Urban sprawl usually has negative connotations, associated with the generation or intensification of complex urban problems, such as land, water, and air pollution, with their consequent negative impacts on human health

Modul ini adalah pedoman atau panduan dalam Proses Belajar dan Mengajar yang merupakan penunjang Praktikum mata Kuliah Probabilitas dan Statistika menggunakan Microsoft Excel dan R-Software, bagi mahasiswa Sekolah Tinggi Manajemen & Informatika (STMIK) Sumedang. Modul ini diharapkan dapat membantu mahasiswa dalam mempersiapkan dan mengikuti proses belajar dan mengajar dengan baik, terarah dan terencana.

My talk at the  Department of Political Science of the University of Michigan about Data Visualization with R. I will talk about the packages and the methods that can be used in R for Data Visualization. I will talk about how we can construct interactive graphs with R.  This talk will hold on March 29th, 2017, 12:00-1:30 pm at 5670 and 5769 Haven Hall,

A common question asked by researchers using regression models is, What sample size is needed for my study? While there are formulae to estimate sample sizes, their assumptions are often not met in the collected data. A more realistic approach to sample size determination requires more information such as the model of interest, strength of the relations among the variables, and any data quirks (e.g., missing data, variable distributions, variable reliability). Such information can only be incorporated into sample size determination methods that use Monte Carlo (MC) methods. The purpose of this article is to demonstrate how to use a MC study to decide on sample size for a regression analysis using both power and parameter accuracy perspectives. Using multiple regression examples with and without data quirks, I demonstrate the MC analyses with the R statistical programming language.

The mean function is a central object of inquiry in the analysis of functional data. Typical questions related to the mean function include quantifying estimation uncertainty, testing parametric models, and making comparisons between populations. To make probabilistic statements about the mean function over its entire domain, rather than at a single location, it is necessary to infer all of its values simultaneously. Pointwise inference is not appropriate for this task and indeed produces anticonservative results, i.e., the coverage level of confidence regions is too low and the significance level of hypothesis tests too high. In contrast, simultaneous confidence bands (SCB) provide a flexible framework for conducting simultaneous inference on the mean function and other functional parameters. They also offer powerful visualization tools for communicating analytic results to interdisciplinary audiences. The construction of SCB in the context of functional data requires specific theory and methods. In particular it is not addressed by the nonparametric regression literature. Although software is available to perform individual steps of an SCB procedure, resources that provide end-to-end computations are scarce. Applications of SCB to one-and two-sample inference are illustrated here with the R package SCBmeanfd. *

The aim of this paper is to show how numerical and statistical methods can be used in order to price derivatives. In particular, the analysis is focused on the pricing of European call and put options of Amazon by means of different techniques. Furthermore, the paper presents with a critical view the Black & Scholes results and its fundamental assumptions, trying to find methods that allow for relaxing these (often) too strong assumptions and to improve the quality of options' prices. Beginning with a brief introduction of the company and its core business, I proceed with the central part of the paper, which is based on the Black & Scholes Model for option pricing and on the Monte Carlo approach. Then, I consider also alternative models that make use of mean reverting processes, and I conclude with the implementation of Lévy processes for option pricing. Finally, I suggest two simple alternative portfolio strategies based on agent's expectations.
(Everything has been done using the R software)

Summary: dendextend is an R package for creating and comparing visually appealing tree diagrams. dendextend provides utility functions for manipulating dendrogram objects (their color, shape and content) as well as several advanced methods for comparing trees to one another (both statistically and visually). As such, dendextend offers a flexible framework for enhancing R's rich ecosystem of packages for performing hierarchical clustering of items.

Availability and implementation: The dendextend R package (including detailed introductory vignettes) is available under the GPL-2 Open Source license and is freely available to download from CRAN at: (http://cran.r-project.org/package=dendextend)

Contact: [email protected]

Ecologically Valuable Areas play an important role in providing ecosystem services, however, human activities such as land conversion and urban sprawl pose pressures and threats to these areas. The study assessed the land use/land cover and urban sprawl in the Mount Makiling Forest Reserve (MMFR) Watersheds and Buffer Zone from 1992 to 2015 using remote sensing and Geographic Information System (GIS). Results showed that the land use/cover within the MMFR buffer zone has changed from 1992 to 2015 with built-up areas increasing by 117% despite Proclamation 1257, s. 1998 which regulates human activities in the zone. Based on the Shannon entropy analysis the land development in the MMFR buffer zone tends to be dispersed and sprawling. However, when the magnitude of change of urban sprawl in the buffer zone from 2002 to 2015 was calculated, a decrease in the entropy value was observed which implies a compacting pattern as the human settlement in the buffer zone increases over time. Proc...

Trois scripts R adaptés à l'utilisation comme traitement QGis permettent de modéliser directement les couches de données SIG contenant un attribut temporel. La modélisation utilise l'équation intégro-différentielle (IDE) et peut prendre en compte un noyau invariant spatialement ou bien un noyau variant spatialement.

This article provides a summary of a selection of some of the high-performance parallel packages (libraries) available from the Comprehensive R Archive Network (CRAN) using the statistical software R. These packages can utilize multicore systems often found in modern personal computers as well as computer cluster or grid computing in order to provide linear speed up the computations in many of advanced statistical modern applications. Some illustrative R parallel codes are given in order to introduce the reader to some basic ideas about parallel programming in R packages.

Introducción Tal como hemos señalado en otra ocasiones, la limpieza y procesamiento de datos es una de las actividades que más tiempo consume en el proceso de análisis de datos. En algunos casos toma hasta el 75% del tiempo total del análisis. No es posible desarrollar procedimientos generales para automatizar completamente el procedimiento porque cada base de datos, cada marco de datos puede presentar malformaciones particulares. Sin embargo, en ocasiones, cuando la data procede de un mismo lugar, es posible que los problemas sean semejantes en los diversos marcos de datos. En este ejercicio, y como parte del anállisis de entorno que adelantamos, comparto los procedimientos que he seguido para limpiar datos obtenidos desde la página web de la OPEP. Una vez más, la aproximación que he tomado para limpiar la data no es necesariamente la mejor, ni la más elegante, para cada caso, pero me han sido útiles para obtener la data en la forma en que la necesito para el análisis.

Data loggers that measure acceleration are regularly used to quantify the behavioural energetics of animals. Calculating dynamic body acceleration (DBA) by smoothing acceleration data using a necessarily long-running mean of e.g. ≥1 s (the DBA method) is not appropriate for determining behaviour duration. In fact, the DBA method results in the elongation of behaviour durations (mean ± 95% CI behaviour duration elongation for scallops [n = 10 animals] and humans [n = 10 free-ranging aquatic biologists]: 508.5 ± 277.2 and 19.3 ± 1.1%, respectively) and consequently an overestimation of energy expenditure (mean ± 95% CI activity metabolic rate overestimation: 212.5 ± 48.0 and 6.12 ± 0.34%, for scallops and humans, respectively; overall metabolic rate overestimation: 91.1 ± 29.9 and 4.18 ± 0.20%, for scallops and humans, respectively). Behaviour duration elongation is of greatest significance when behaviour durations are short (minimum, mean and maximum single behaviour duration for scallops and humans recorded in this study: 0.12 and 0.37, 0.40 and 8.04, 0.84 and 185.73 s, respectively). Overestimation of the duration of behaviours naturally causes errors in the calculations of behavioural time–energy budgets for all species that move intermittently, as demonstrated for scallops, crabs, ‘amphibious’ signal crayfish and humans. Furthermore, behaviours of any duration should be accurately detected, quantified and when appropriate, the behaviour type should be identified. The R package BEnergetix can quickly calculate accurate invertebrate and vertebrate behavioural time−energy budgets from acceleration, metabolic rate and environmental data.

Ecologically Valuable Areas play an important role in providing ecosystem services, however, human activities such as land conversion and urban sprawl pose pressures and threats to these areas. The study assessed the land use/land cover and urban sprawl in the Mount Makiling Forest Reserve (MMFR) Watersheds and Buffer Zone from 1992 to 2015 using remote sensing and Geographic Information System (GIS). Results showed that the land use/cover within the MMFR buffer zone has changed from 1992 to 2015 with built-up areas increasing by 117% despite Proclamation 1257, s. 1998 which regulates human activities in the zone. Based on the Shannon entropy analysis the land development in the MMFR buffer zone tends to be dispersed and sprawling. However, when the magnitude of change of urban sprawl in the buffer zone from 2002 to 2015 was calculated, a decrease in the entropy value was observed which implies a compacting pattern as the human settlement in the buffer zone increases over time. Proc...

This is a case study that compares a number of spatial estimation models (such as ordinary kriging, block kriging, universal kriging, kriging with external drift and conditional simulation) to interpolate the total rainfall of 2009 for the Manawatu River Catchment using 61 rain gauges. The accuracy of the spatial models were determined by variance and the maintenance of the distinct rainfall pattern. Before the performance of the models were tested, the statistical and spatial statistical characteristics of the rainfall data of the 61 rain gauges were determined. The frequency histograms (including with transformations like square root, log, log 10, etc.) showed that the data is right skewed. The visual spatial structure revealed cluster of rain gauges at the Ruahine and Tararua Ranges with large recorded quantity of rainfall representing orographic rainfall. The variogram maps showed that the rainfall of 2009 is isotropic. Additionally, the relationship between rainfall and elevation was explored with scatterplots. The plot revealed a weak relationship. Therefore elevation was not applied in the spatial estimation method as an auxiliary data set but the y coordinate was used in the kriging with external drift technique. 

The modelling of the 2009 rainfall data set started with fitting an empirical variogram model. The pentaspherical model was the best fit for this data set. Secondly, a regular grid of 100 meters was established for the interpolation methods. Thirdly, the interpolation methods were applied to the rainfall data set by computing the rainfall and variance surfaces. The performance tests (variance and maintenance of the distinct rain pattern) revealed that block kriging is the best spatial prediction method because this method met both requirements (lowest mean variance and the maintenance of the distinct pattern of 2009 rainfall).

We built a fuel price database from aproximately 20.000 Italian retailers and displayed the dynamic price distribution in 2014-2016. Price distribution over time results in a three dimentional graph allowing a quick grasp of fuel price policies at both national and local level; further insights are provided by separating the prices of branded and independent retailers. Our representation shows the diversified nature of the Italian fuel retail sector, including separate price settings in the different areas, from macro areas to provinces. The results reveal multi-modal distributions for gasoline and diesel in served mode and separate distributions for branded and independent retailers, indicating different price policies notably in the Central and Southern areas of the peninsula. This empirical distribution of the prices over time can be a useful visual analytical tool for describing the fuel retail sector and assist the policymaker in its restructuring.

Diversity and activity patterns of medium and large mammals in La Encrucijada Biosphere Reserve, Chiapas, Mexico. In Mexico, wetlands occupy an important portion of the country, among them, mangroves are particularly diverse. La Encrucijada Biosphere Reserve (ENBIRE) is a coastal ecosystem of mangrove located along the Pacific Coastal Plain in the Southwestern portion of Chiapas state. The ENBIRE mangroves are among the most important of the American Pacific Coast, highlighting the role they play in the maintenance of the community of mammals on the coast of the state. There are few studies in Mexico related to the mammals associated with these ecosystems, our aim was to estimate the diversity and activity patterns of medium and large mammals in the ENBIRE. Sampling was conducted from August 2015 to August 2016 using camera traps. We obteined 1 851 independent photographs records, with a total sampling effort of 5 400 trap-days. Nineteen species of mammals were registered belonging to 15 families and seven orders, and five species were new records to the area. Six species present are listed, two as endangered and four as threatened.
Interpolation and extrapolation analyzes showed an asymptotic trend in the curves for the rainy and dry seasons. The coverage of the sample for both seasons was 99.9 % and 99.8 %, respectively, indicating that both cases were a representative sample. According to the relative abundance index obtained, the most abundant species were Procyon lotor (IAR = 4.35), Nasua narica (IAR = 3.91), Philander opossum (IAR = 2.04), Cuniculus paca (IAR = 1.89), Didelphis marsupialis (IAR = 1.67) and Dasypus novemcinctus (IAR = 1.02). In terms of patterns of activity C. paca, P. opossum, D. marsupialis and D. novemcinctus were primarily nocturnal; P. lotor showed a tendency towards nocturnal habits but was also recorded during the day; N. narica was mainly diurnal. This information can be useful to the creation of management programs and the conservation of medium and large mammals in the ENBIRE, especially for species at risk