similar to: ellipse

Hi all, I'm intersted in draw confidence regions for two estimates that *are not* in the same GLM, but I know their point estimates c(a,b) and their covariance matrix V, say. Of course > V[1,2]==V[2,1] [1] TRUE Their joint distribution is not binormal (at least i don't know it), but I know (or I assume) their limiting distribution is Normal, so I can use the bivariate Wald statistics to

Hi, I'm using the R library(car) to draw confidence/prediction ellipses in a scatterplot. >From what i understood the ellipse() function return an ellipse based parameters: shape, center, radius . If i read dataEllipse() function i can see how these parameters are calculated for a confidence ellipse. ibrary(car) a=c(12,12,4,5,63,63,23) b=c(13,15,7,10,73,83,43) v <-

I have been using the ellipse function from the car package and the covariance matrix to draw an ellipse around a group of points to show the confidence limits. However, the points are actually represented by 3 variables so rather than plot each pairwise combination of variables in 2D I would like to plot the 'ellipse' in 3D using the djmrgl package. Can anyone offer advice on how I can

Hi, I have to construct an ellipse interval region on a PCAbiplot, I have my parameters "a" and "b" and I would apply the formula: draw.ellipse(x, y, a = , b = ) I have done a PCA on my data so I have my scores and loading for the first and second component, but my answer is what I have to choose as X and Y into the formula? if "a" and "b" are scalars or

Dear R users: I have a dataset with two variables (>20000 observations, two samples from same subject) and I used "kernSur" from library(Genkern) to get a estimated bivariate density and corresponding plots as follows: new.data.normal<-data.normal[!is.na(data.normal[,2]),] x<-new.data.normal[,2] y<-new.data.normal[,3] op <- KernSur(x,y, xgridsize=50, ygridsize=50,

Hello, SAS' point and click interface has the option of produce a scatterplot with a superimposed confidence ellipse for the correlation coefficient. Since I generally like R so much better, I would like to reproduce this in R. I've been playing with the ellipse package. In order to have the points and the ellipse on the same graph I've done the following. (Load ellipse

I can take the results of a simulation with one random variable and generate an empirical interval that contains 95% of the observations, e.g., x <- rnorm(10000) quantile(x,probs=c(0.025,0.975)) Is there an R function that can take the results from two random variables and generate an empirical ellipse that contains 95% of the observations, e.g., x <- rnorm(10000) y <- rnorm(10000) ?

Hello, R-Help - I am trying to plot the results of an ordination from package vegan. The tricky part for me right now is getting the colors of the ellipses denoting the 95% confidence intervals of the group centroids to match the colors of the points for those same groups. >From and earlier post, I saw the code to make a plot of the ordination using different colors for my different groups.

Hello everyone I really need some help here. I made a confidence ellipse using the function ellipse from the package ellipse: ellipse(SD, centre=colMeans(pcsref),t=sqrt((p * (n-1)/(n-p))*qf(0.99, p,n-p)) Now, I want to write a function whom return TRUE or FALSE if a given observation is in the confidence ellipse. But I have no clue how to do it Can anyone help me? Best regards Jessica

Hi, I created a principal component plot using the first two principal components. I used the function princomp() to calculate the scores. now, I would like to superimpose an ellipse representing the center and the 95% confidence interval of a series of points in my plot (as to illustrate the grouping of my samples). I looked at the ellipse() function in the ellipse package but can't get it

Hi: Does Ellipse and dataellipse function in R produce the same ellipse? I wanted to see how the radius for the Ellipse function in R calculated. Also what is the var-covariance matrix, if any, assumed for the dataellipse function? Heres an example of the code where I am generating Multivariate normal data and creating ellipse using the 2 functions: library(car) library(mvtnorm) mu =

I have a 3xN matrix of parameters obtained from N regressions where the 3 parameters are jointly statistically significant. I would like to reproduce a 3D confidence ellipsoid projecting 2D ellipses onto the XY plane as in Figure 5.2 in this

Hi!, I made a plot with two variables representing the first two axis of a principle component analysis. My question is: How can I superimpose on such plot an ellipse that represent the 95% interval of confidence of scores? Best regards, Paula -- Lic. Paula Gonzalez Divisi??n Antropolog??a Museo de La Plata. Facultad de Ciencias Naturales y Museo. UNLP. Paseo del Bosque s/n?? - B1900FWA - La

Dear All, I would be very appreciative of your help with the following 1). I am running multivariate multiple regression through the manova() function (kindly suggested by Professor Venables) and getting two different answers for test=c("Wilks","Roy","Pillai") and tests=c("Wilks","Roy",'"Pillai") as shown below. In the

After a lot of effort I developed the following function to compute the bounding ellipse (also known a as minimum volume enclosing ellipsoid) for any set of points. This script is limited to two dimensions, but I believe with minor modification the algorithm should work for 3 or more dimensions. It seems to work well (although I don't know if can be optimized to run faster) and

I have empirical Bayes estimates for slopes and intercepts for a number of subjects and I would like to plot the slopes and intercepts with confidence ellipses. These ellipses would be based on the confidence intervals for the slope and intercepts (forming the major and minor axis of each ellipse), and the correlation in the slope and intercepts. The ellipse function in the car library

The mvee() function is intended to be released under the BSD license. Copyright (c) 2009, Nima Moshtagh Copyright (c) 2011, Andy Lyons All rights reserved. http://www.opensource.org/licenses/bsd-license.php Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: Redistributions of source code must

Full_Name: Volker Franz Version: Version 1.6.2 (2003-01-10) OS: Debian Submission from: (NULL) (192.124.28.104) Hi there, it seems to me that data.ellipse of package "car" (Version 1.0-1) produces confidence interval's which are too big. To see this, do: library(car) plot(c(-2,2),c(-2,2),pch=0) data.ellipse(rnorm(10000),rnorm(10000),levels=0.68,plot.points=F) abline(v=+1)

That's probably a stupid question, but I'm looking for a low-level command which plots ellipse, specifying only center and deformation axes. The purpose is to illustrate bivariates gaussians with 2D .95 confident levels without using any specific library. Thanxs for your help, Guillaume

Many thanks to Andy Liaw for quickly reminding me of "ellipse" package in CRAN. It is apparently what I wanted. Not sure whether it will work in S-PLUS or not. But I will give it a try. Thank you. Paul. > > Have you checked CRAN? There's an "ellipse" package on CRAN for quite a > while. > > Andy > > > -----Original Message----- > > From: