search for: enfa

Dear all, I am currently running an ENFA in R using Adehabitat pkg to assess species distribution and I am really stuck and need some help to finalize my project. I run the ENFA in both original location data and pseudo-absence points (the latter randomly generated using dismo pkg), and now I would like to assess the performance of the E...

Dear all, I am running an Ecological Niche Factor Analysis in R but I am stuck with a problem. As soon as I ask the software to compute the ENFA, I get the following error message: Error in eigen(Se) : infinite or missing values in 'x' Does anyone know what could be wrong. I do not have missing values in my dataset. Please follow the codes I used for my analysis so far: library (adehabitat) library (ade4) (dataenfa1 <- da...

Hello: I have an two factorial random block design. It's a ecology experiment. My two factors are, guild removal and enfa removal. Both are two levels, 0 (no removal), 1 (removal). I have 5 blocks. But within each block, it's unbalanced at plot level because I have 5 plots instead of 4 in each block. Within each block, I have 1 plot with only guild removal, 1 plot with only enfa removal, 1 plot for control with no...

Dear All, I have a set of environental maps and presence-only points for some species. How can I generate distributions models on R using these presence-only data? What packages and functions can I use to do so? Kind regards, Miltinho Brazil [[alternative HTML version deleted]]

...and stores is into a data frame. 'traj2spdf' converts an object of class 'traj' into an object of class 'SpatialPointsDataFrame'. 'traj2sldf' converts an object of class 'traj' into an object of class 'SpatialLinesDataFrame'. - The function enfa() has been modified: The old components "co" and "l1" have been removed from objects of class "enfa", as they did not rely on solid mathematical theory. The old component "c1" is now named "co", and corresponds to the scores of habitat va...

...and stores is into a data frame. 'traj2spdf' converts an object of class 'traj' into an object of class 'SpatialPointsDataFrame'. 'traj2sldf' converts an object of class 'traj' into an object of class 'SpatialLinesDataFrame'. - The function enfa() has been modified: The old components "co" and "l1" have been removed from objects of class "enfa", as they did not rely on solid mathematical theory. The old component "c1" is now named "co", and corresponds to the scores of habitat va...

...ar all, I have just uploaded a package to CRAN a new package called 'adehabitat'. This package is intended for ecologists who want to analyse the use of space by animals. Many functions currently used in this field are available to highlight habitat selection by animals (selection ratios, ENFA, habitat suitability maps with the algorithm DOMAIN or Resource Selection Functions) or to describe the movements and area used in radio-tracking studies (kernel or minimum convex polygon home range, computation of travel speed and turning angles). ASCII raster maps exported from Arcview can als...

...ull, brownian bridge approach for kernel estimation), estimation of schoener's ratio. This package now allows a better management of objects of class "area" (see plot.area, perarea, ararea). Some arguments of the graphical functions have also been changed (kernel, image.kasc, scatter.enfa). Finally, some minor bugs have been corrected. Note that the package now need that the packages ade4 and gpclib are installed. Questions, comments and suggestions are greatly appreciated. Happy testing, Cl?ment Calenge. ====================================== Cl?ment CALENGE LBBE - UMR CNRS 55...

...cmap() converts one factor map into a set of maps giving the distance to the patches belonging to the different levels. - The kernel home-range estimation can now be fitted using an Epanechnikov kernel (though it is still optional), resulting in a quicker estimation. - The former function enfa() has been modified. It now requires a data frame (available units) and a vector (use of each unit). If the data consist of a point pattern and of an object kasc, the function data2enfa is to be used before. - The function angles() now takes an argument indicating how successive relocati...

Dear all, I have just uploaded to CRAN the version 1.5 of the package 'adehabitat'. Significant changes are listed below: * the package now contains a new function allowing a factorial decomposition of the Mahalanobis distances in habitat selection studies, named madifa(). * The ENFA can now be performed using all kinds of variables (numeric, factors, fuzzy, mixing of several types, etc.) * Several methods allowing the analysis of animals movements have been added, including the first passage time (function fpt()), a rediscretization algorithm (redisltraj()), and an interac...

...ar all, I have just uploaded a package to CRAN a new package called 'adehabitat'. This package is intended for ecologists who want to analyse the use of space by animals. Many functions currently used in this field are available to highlight habitat selection by animals (selection ratios, ENFA, habitat suitability maps with the algorithm DOMAIN or Resource Selection Functions) or to describe the movements and area used in radio-tracking studies (kernel or minimum convex polygon home range, computation of travel speed and turning angles). ASCII raster maps exported from Arcview can als...

...ull, brownian bridge approach for kernel estimation), estimation of schoener's ratio. This package now allows a better management of objects of class "area" (see plot.area, perarea, ararea). Some arguments of the graphical functions have also been changed (kernel, image.kasc, scatter.enfa). Finally, some minor bugs have been corrected. Note that the package now need that the packages ade4 and gpclib are installed. Questions, comments and suggestions are greatly appreciated. Happy testing, Cl?ment Calenge. ====================================== Cl?ment CALENGE LBBE - UMR CNRS 55...

...cmap() converts one factor map into a set of maps giving the distance to the patches belonging to the different levels. - The kernel home-range estimation can now be fitted using an Epanechnikov kernel (though it is still optional), resulting in a quicker estimation. - The former function enfa() has been modified. It now requires a data frame (available units) and a vector (use of each unit). If the data consist of a point pattern and of an object kasc, the function data2enfa is to be used before. - The function angles() now takes an argument indicating how successive relocati...

Dear all, I have just uploaded to CRAN the version 1.5 of the package 'adehabitat'. Significant changes are listed below: * the package now contains a new function allowing a factorial decomposition of the Mahalanobis distances in habitat selection studies, named madifa(). * The ENFA can now be performed using all kinds of variables (numeric, factors, fuzzy, mixing of several types, etc.) * Several methods allowing the analysis of animals movements have been added, including the first passage time (function fpt()), a rediscretization algorithm (redisltraj()), and an interac...

...package contains several demo files to allow an overview of these parts : demo(rastermaps), demo(homerange), demo(managltraj), demo(analysisltraj), demo(nichehs). * the package now contains a new function allowing the exploration of the ecological niche, which generalizes several factor analyses (ENFA, MADIFA, ...) and is closely related to several methods (Mahalanobis distances, selection ratios, etc.), named gnesfa() (see the examples of the help page for the properties of this analysis). * The class ltraj now distinguishes two types of trajects: type I (time not recorded, e.g. tracks of anim...

...package contains several demo files to allow an overview of these parts : demo(rastermaps), demo(homerange), demo(managltraj), demo(analysisltraj), demo(nichehs). * the package now contains a new function allowing the exploration of the ecological niche, which generalizes several factor analyses (ENFA, MADIFA, ...) and is closely related to several methods (Mahalanobis distances, selection ratios, etc.), named gnesfa() (see the examples of the help page for the properties of this analysis). * The class ltraj now distinguishes two types of trajects: type I (time not recorded, e.g. tracks of anim...