similar to: generate correlated dataset

Displaying 20 results from an estimated 5000 matches similar to: "generate correlated dataset"

2003 Jul 11
2
using SVD to get an inverse matrix of covariance matrix
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]
2008 Nov 11
1
simulate data with binary outcome and correlated predictors
Hi, I would like to simulate data with a binary outcome and a set of predictors that are correlated. I want to be able to fix the number of event (Y=1) vs. non-event (Y=0). Thus, I fix this and then simulate the predictors. I have 2 questions: 1. When the predictors are continuous, I can use mvrnorm(). However, if I have continuous, ordinal and binary predictors, I'm not sure how to simulate
2007 Sep 17
1
Create correlated data with skew
Hi all, I understand that it is simple to create data with a specific correlation (say, .5) using mvrnorm from the MASS library: > library(MASS) > set.seed(1) > > a=mvrnorm( + n=10 + ,mu=rep(0,2) + ,Sigma=matrix(c(1,.5,.5,1),2,2) + ,empirical=T + ) > a [,1] [,2] [1,] -1.0008380 -1.233467875 [2,] -0.1588633 -0.003410001 [3,] 1.2054727 -0.620558768
2012 Jul 04
2
How to generate a correlated binary data set?
Hi. I am trying to generate a correlated binary data set. I've tried to use mvtBinaryEP, binarySimCLF, and bindata packages but none of them works in R version 2.15.1. Do you know any package to generate correlated binary covariates and work in R version 2.15.1, or how to generate it? Thanks, [[alternative HTML version deleted]]
2009 Feb 02
2
how to generate multiple random variables that are correlated
Hi. I have two variables, x and y, that are each normally distributed with mean 0 and have known standard deviations. The variables also have a known correlation, so I can represent their correlations in a matrix like so: a <- array(c(0.3,0.1,0.1,0.2),c(2,2)) a Is there an R function that generates random values for my two variables given the correlation? I'd like to do this for up to
2012 Dec 02
2
How to simulate correlated data
Hello there, I would like to simulate X --Normal (20, 5) Y-- Normal (40, 10) and the correlation between X and Y is 0.6. How do I do it in R? Thank you very much ----- TO GET MORE DETAILS CLICK HERE -- View this message in context: http://r.789695.n4.nabble.com/How-to-simulate-correlated-data-tp4651667.html Sent from the R help mailing list archive at
2005 Dec 15
5
How to simulate correlated data
Hello there, I would like to simulate X --Normal (20, 5) Y-- Normal (40, 10) and the correlation between X and Y is 0.6. How do I do it in R? Thank you very much Lisa Wang Msc. Princess Margaret Hospital Toronto, Ca
2005 Dec 01
1
Simulate Correlated data from complex sample
Dear List: I have created some code to simulate data from a complex sample where 5000 students are nested in 50 schools. My code returns a dataframe with a variable representing student achievement at a single time point. My actual code for creating this is below. What I would like to do is generate a second column of data that is correlated with the first at .8 and has the same means within
2011 Aug 11
5
generate two sets of random numbers that are correlated
Dear R users I'd like to generate two sets of random numbers with a fixed correlation coefficient, say .4, using R. Any suggestion will be greatly appreciated. Regards, Kathryn Lord -- View this message in context: http://r.789695.n4.nabble.com/generate-two-sets-of-random-numbers-that-are-correlated-tp3735695p3735695.html Sent from the R help mailing list archive at Nabble.com.
2003 Dec 03
1
Simulating correlated distributions
Hi How can one simulate correlated distributions in R for windows? Coomaren P. Vencatasawmy --------------------------------- Download Yahoo! Messenger now for a chance to WIN Robbie Williams "Live At Knebworth DVD" [[alternative HTML version deleted]]
2007 Jun 12
4
Generating artificial datasets with a specific correlation coefficient.
I need to create artificial datasets with specific correlation coefficients (i.e. a dataset that returns r = 0.30, etc.) as examples for a lab I am teaching this summer. Is there a way to do that in R? Thanks. Jim Milks Graduate Student Environmental Sciences Ph.D. Program 136 Biological Sciences Wright State University 3640 Colonel Glenn Hwy Dayton, OH 45435 [[alternative HTML version
2010 Feb 28
1
Gradient Boosting Trees with correlated predictors in gbm
Dear R users, I’m trying to understand how correlated predictors impact the Relative Importance measure in Stochastic Boosting Trees (J. Friedman). As Friedman described “ …with single decision trees (referring to Brieman’s CART algorithm), the relative importance measure is augmented by a strategy involving surrogate splits intended to uncover the masking of influential variables by others
2007 Nov 16
1
generate multivariate F with specified correlation matrix
Dear all, In MATLAB, to generate multivariate F with specified correlation matrix Pn I can use the code such as Z = mvnrnd([0 0 0 0 0], Pn, N); U = normcdf(Z,0,1); X = [finv(U(:,1),5,15) finv(U(:,2),5,15) finv(U(:,3),5,15) finv(U(:,4),5,15) finv(U(:,5),5,15)]; Is there something similar in R? Thank you for your time.
2009 Feb 12
3
get top 50 correlated item from a correlation matrix for each item
Hi, I have a correlation matrix of about 3000 items, i.e., a 3000*3000 matrix. For each of the 3000 items, I want to get the top 50 items that have the highest correlation with it (excluding itself) and generate a data frame with 3 columns like ("ID", "ID2", "cor"), where ID is those 3000 items each repeat 50 times, and ID2 is the top 50 correlated items with ID,
2010 Aug 24
3
generate random numbers from a multivariate distribution with specified correlation matrix
Hi all, rmvnorm()can be used to generate the random numbers from a multivariate normal distribution with specified means and covariance matrix, but i want to specify the correlation matrix instead of covariance matrix for the multivariate normal distribution. Does anybody know how to generate the random numbers from a multivariate normal distribution with specified correlation matrix? What about
2010 Jan 21
1
correlation significance testing with multiple factor levels
[Apologies in advance if this is too "statistics" and not enough "R".] I've got an experiment with two sets of treatments. Each subject either received all treatments from set A or all treatments from set B. I can compute the N pairwise correlations for all treatments in either set using cor(). If I take the mean of these N pairwise correlations, I see that the effects
2011 May 07
1
generate multiple mvrnorm samples using apply-like
I want to generate multiple multivariate normal samples with different mean vectors and common covariance matrix. I can do this with a loop, but can't quite figure out how to do it with apply and friends. In the example below, I want values to have 3 columns: group, x, y # number of groups, and group means x <- jitter(seq(2,10,by=2)) y <- x + rnorm(length(x), 0, .5) means <-
2004 Jun 25
2
Simulating from a Multivariate Normal Distribution Using a Correlation Matrix
Hello, I would like to simulate randomly from a multivariate normal distribution using a correlation matrix, rho. I do not have sigma. I have searched the help archive and the R documentation as well as doing a standard google search. What I have seen is that one can either use rmvnorm in the package: mvtnorm or mvrnorm in the package: MASS. I believe I read somewhere that the latter was
2008 Jun 16
0
Creating correlated multivariate dataset
Hello list, I am trying to test a model but for the beginning I want to do this by using simulated dataset. The model is Y_t = X_t %*% beta + e Where Y : (Nx1); X: (Nxp); beta: (0.6,0.3,0.1); e-uncorrelated normally distributed variates for each t. and later I want to use to use this dataset in a BUGS model to estimate the betas. Thank you for you consideration. [[alternative
2007 Mar 23
1
generating lognormal variables with given correlation
Dear R users I use simulated data to evaluate a model by sampling the parameters in my model from lognormal distributions. I would like these (lognormal distributed) parameters to be correlated, that is, I would like to have pairwise samples of 2 parameters with a given correlation coefficient. I have seen that a covariance matrix can be fixed when generating random variables from a