similar to: plotting data with ellipse confidence intervals

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 <-

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

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

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)

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

List, Would someone be so kind as to point me to a function that will calculate simultaneous confidence intervals of regression coefficients based upon their distribution as (under the assumption of normal errors, with \mathbf{X} as the design matrix): $\hat{\mathbf{\beta}} \sim N(\mathbf{\beta}, \sigma^2(\mathbf{X}^T\mathbf{X})^{-1})$. 'confint' calculates individual coefficients so

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

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.

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 list members, This might be a silly question but I just can't figure it out. I am using the "ellipse" package on covariance matrices. I would simply like to plot my ellipses WITH its two axis ploted as well. These axis represents the 2 eigen vectors of my matrix and it is important that I can graphically show them. Is there an easy way to do so? Many thanks, Antoine -- View

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: 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 =

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

Hi - I am using R version 2.13.0. I have run several GLMMs using the glmmPQL function to model the proportion of fish caught in one net to the total caught in both nets by length. I started with a polynomial regression full model with three length terms: l, l^2, and l^3 (l=length). The length terms and intercept were the fixed effects and the random effect was a paired haul (n=18).

Hello, has anybody written a function to plot density ellipses (95%, 99% or anything) in a scatterplot? I found nothing in any package, nor in the list archives. There does seem to be a contributed package "ellipse" for S-Plus (on S-Archive), but it does a lot more than what I would need. Still, if anybody ported it to R, I'd be grateful for a link. I'm a bit afraid to try the

Hi, I used to get a really useful graph when I ran the following command using the MASS library: > cov.rob(cbind(dekeyser$AGE,dekeyser$GJTSCORE),cor=T) Besides the regular output, a graph appeared that had the classical correlation and the robust correlation, and two ellipses, one surrounding the data that would be used in the classical correlation and the other surrounding the data in the

library (ellipse) shape1 = c (1, 0, 0,1) dim(shape1) = c(2,2) ellipse (center = c(0,0), shape = shape1, radius = 1) ============================= Error in plot.xy(xy.coords(x, y), type = type, col = col, lty = lty, ...) : plot.new has not been called yet It is really frustrating. Also what do the shape matrix, radius correspond to an ellipse function (x-x0)^2/a + (y-y0)^2/b = 1 ?

Dear mailing list, I have following array: X2 Y2 [1,] 422.7900 6.0 [2,] 469.8007 10.5 [3,] 483.9428 11.0 [4,] 532.4917 25.5 [5,] 596.1942 33.5 [6,] 630.8496 40.5 [7,] 733.2996 45.0 [8,] 946.4779 32.0 [9,] 996.8068 35.5 [10,] 1074.3310 23.0 I do afterwards the following: plot.new() plot.window(xlim=c(min(X1)-50,max(X1)+50),

hi,R users, Now I have some scatter figures, is there some method can plot equalprobable error ellipse ? -- TANG Jie Email: totangjie@gmail.com Tel: 0086-2154896104 Shanghai Typhoon Institute,China [[alternative HTML version deleted]]

Hello, I'm developing an ordination using metaMDS (package vegan). The analysis identifies 3 distinct groups that I'd like to define by either adding circles or ellipses to help identify the groups. The data set is a spatial temporal data base depicting change in each of 4 areas over 3 time periods. I can add lines that would link each of the time - x - area trajectories, but