similar to: Relationship between covariance and inverse covariance matrices

I've only been using R on and off for 9 months and started using the glasso package for sparse covariance estimation. I know the concept is to shrink some of the elements of the covariance matrix to zero. However, say I have a dataset that I know has some underlying "baseline" covariance/correlation (say, a value of 0.3), how can I change or incorporate that into to the

Hello, I have a data set with 9700 records, and 7 parameters. The data were collected for a survey of forest communities. Sample plots (1009) and species (139) are included in this data set. I need to determine how species are accumulated as new plots are considered. Basically, I want to develop a species area curve. I've included the first 20 records from the data set. Point

Sorry if this is a stupid question but I've been stuck on how to code so that I can order rows of a matrix without paying attention to the diagonal elements. Say, for example, I have a matrix d: > d [,1] [,2] [,3] [,4] [1,] 0.000000 2.384158 2.0065682 2.2998856 [2,] 2.384158 0.000000 1.4599928 2.4333213 [3,] 2.006568 1.459993 0.0000000 0.9733285 [4,] 2.299886

Dear R-users, I have one question about using SVD to get an inverse matrix of covariance matrix Sometimes I met many singular values d are close to 0: look this example $d [1] 4.178853e+00 2.722005e+00 2.139863e+00 1.867628e+00 1.588967e+00 [6] 1.401554e+00 1.256964e+00 1.185750e+00 1.060692e+00 9.932592e-01 [11] 9.412768e-01 8.530497e-01 8.211395e-01 8.077817e-01 7.706618e-01 [16]

Full_Name: Gang Liang Version: 1.7.1 OS: Debian/Woody Submission from: (NULL) (192.6.19.190) > print(arima.sim(list(ar=.3,order=c(1,1,1)), 30)) [1] 0.00000000 0.10734243 0.02907301 -1.23441659 -0.98819317 -2.82731975 [7] -2.69052512 -4.22884756 -5.02820635 -5.41514613 -6.20486350 -7.01040649 [13] -6.78121289 -5.41111810 -4.96338053 -5.42395408 -6.22741444 -5.75228153 [19] -6.07346580

Dear All, I would like to ask a couple of questions on a LME model. I tested 4 selection lines at 4 food concentrations against a standard competitor stock. I had 3 replicate cages per selection line. In each cage I have 10 vials. I counted the number of wild type flies and competitor stock emerging in each vial. My main question is: is there any difference between selection lines? I did fit

Using functions how would I go about do this question? (I already have a mean defined for a function of x.) Write a function called MyMean2. This function has two arguments, x and nonzero, where nonzero has the default value TRUE. This function should return the (Previous defined mean of x) if nonzero=FALSE (Previous defined mean of x) for all x's>0 if nonzero=TRUE Much appreciated.

Dear List, I'm getting weird and unexpected behaviour using time and %%, or %/%. It's likely I'm not appreciating the nuances of floating point arithmetic. Or it could be a bug. I'm running > R.version _ platform x86_64-redhat-linux-gnu kernel 2.6.33.8-149.fc13.x86_64 arch x86_64 os linux-gnu system x86_64, linux-gnu

HI, I would like to extract data in a specific way.  For example, the rainfall data 0,0,1.5,0,0, 3,1,2.5,0,0,0,0, 2.3,0,0,0, 2.1,1.4,0,0,0, 3,2,1,0,0,0... data_1: 1.5, 2.3               ( a single nonzero data between zeros data) data_2: 3.1, 2.5, 2.1,1.4   ( two nonzero data between zeros data) data_3: 3,1,2.5, 3,2,1       ( three nonzero data between zeros data) Thank you so much for any

Hello! I have data containing a large number of probabilities (about 60) of nonzero coefficients to predict 10 different independent variables (in 10 different BMA models). i've arranged these probabilities in a matrix like so: (IV1) (IV2) (IV3) ... p(b0) p(b0) p(b0) p(b1) p(b1) p(b1) p(b2) p(b2) p(b2) ... where p(b1) for independent variable 1 is p(b1 !=

Can someone verify for me if the for loop below is really calculating the nonzero min for each row of a matrix? I have a bug somewhere in the is section of code. My first guess is how I am find the the nonzero min of each row of my matrix. The overall idea is to make sure I am investing all of my money, i.e. new.set is a set of indicator variables for each stock for a particular portfolio, i.e.

Hi, Me a newbie in RoR - switching from .NET. i want to write an application that has a newsletter functionality where I can create an interface where in I can have options to send newsletters to multiple people in the database. i need to make a form which has from hardcoded, to is selected from te database maybe a listbox next to it and then a subject and text area. how wud i go about doing

hello all, i'm trying to use QPmat, from the popbio package. it appears to be based on solve.QP and is intended for making a population projection matrix. QPmat asks for: nout, A time series of population vectors and C, C constraint matrix, (with two more vectors, b and nonzero). i believe the relevant code from QPmat is: function (nout, C, b, nonzero) { if (!"quadprog" %in%

Since notation for state-space models vary, I'll use the following convention: x(t) indicates the state vector, y(t) indicates the vector of observed quantities. State Transition Equation: x(t+1) = Fx(t) + v(t) Observation Equation: y(t) = Gx(t) + w(t) Cov[v(t)] = V Cov[w(t)] = W I've found myself in a situation where I will have V = s%*%t(s)*k^2, with s a vector the same length as the

Hello! I am trying to install R and its says there is an error with the software. I am using the link for Mac OS the most recent version on the website because my Mac OS is M1 and 13.2 version. I am able to download it but then when I install it it says they?re an error with the software that caused the installation to fail. I was wondering what I need to do to install R? Vivian Jungels

Full_Name: Chien-yu Peng Version: 2.0.1 OS: Windows XP Professional Submission from: (NULL) (140.109.72.181) Dear all: Although I don't know you, I am thankful for your help. When I use the function mantelhaen.test for R x C x K (R, C > 2) table, the output is not the same as SAS's. I don't know that the result consist with one of SAS's. But it works correctly for 2

Hello, Are there any plans to add R packages for Ubuntu on other architectures in addition to amd64? We are looking for s390x packages as the version from the distro's package manger is 4.2.2. I'm happy to help in any way I can. Thank you. Regards, Vivian Kong Linux on IBM Z Open Source Ecosystem IBM Canada Toronto Lab [[alternative HTML version deleted]]

Hi, I'm very new to working with sparse matrices and would like to know how I can column permute a sparse matrix. Here is a small example: > M1 <- > spMatrix(nrow=5,ncol=6,i=sample(5,15,replace=TRUE),j=sample(6,15,replace=TRUE),x=round_any(rnorm(15,2),0.001)) > M1 5 x 6 sparse Matrix of class "dgTMatrix" [1,] 2.983 . 1.656 5.003 . . [2,] .

Dear Dr. Bivand and R-users, I have a 5 by 5 grid, say, location[1:5,1:5], and I want to know the indices of 8 neighbours of each cell. For example, for location[2,2], its neighbour coordinates are [1,1:3], [2,1], [2,3] and [3,1:3]. Sometimes I also need to remove edge effects (torus = TRUE). I have tried "cell2nb" function in your spdep package. Here's my example: > neigh

Full_Name: Christian Lederer Version: 1.8.0 OS: Linux Submission from: (NULL) (217.229.7.13) R-1.8.0 seems to calculate wrong covariances, when the argument of cov() is a matrix or a data frame. The following should produce a matrix of zeroes and NaNs: x <- matrix(c(NA ,NA ,0.9068995 ,NA ,-0.3116229, -0.06011117 ,0.7310134 ,NA ,1.738362 ,0.6276125, 0.6615581 ,NA