search for: ericlee100

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

Hi. I'm trying to take the difference in days between two times. Can you point out what's wrong, or suggest a different function? When I try the following code, The following code works fine: a <- strptime(1911100807,format="%Y%m%d%H",tz="GMT") b <- strptime(1911102718,format="%Y%m%d%H",tz="GMT") x <- difftime(b, a,

Hi, I'd like to merge the following list and data frame by matching the first column in the data frame to the first number in each object of the list. I'd also like the merged object to be a list. Any suggestions? Thanks. eric a <- list(c(1,11), c(2,12), c(3,13), c(4,14), c(5,16)) b <- data.frame(1:5, 51:55) [[alternative HTML version deleted]]

Hi, I have data for one dependent variable and multiple independent variables y = b0 + b1*x1 + b2*x2 + ... I want to a list of all models that have some subset of the independents (just x1 x2, and not x3, etc.) and their corresponding BIC values. Is there a pre-existing function that does this? I saw that you can calculate individual BIC values using 'lm' and something like AIC(lm1, k

Hi. I'm trying to plot two ecdf's on the same graph using two different colors. I can plot using the same color, but it doesn't work when I change colors? Any suggestions? Thanks in advance for your help. x <- c(0.80, 0.83, 1.89, 1.04, 1.45, 1.38, 1.91, 1.64, 0.73, 1.46) y <- c(1.15, 0.88, 0.90, 0.74, 1.21) plot(ecdf(x)) # it works without col='blue', but doesn't

Hi, How do I get labels onto the output from tapply? I need the labels to merge the output with another data frame. Thanks. eric d <- data.frame(cbind(x=1:3, y=1:10)) a <- with(d, tapply(y, x, sum)) [[alternative HTML version deleted]]

Hello, I'm trying to use tapply to find group means in a function. It works outside of a function, but I get the error message from the following code: "Error in tapply(index, cluster, mean) : arguments must have same length." Any suggestions? Thanks. eric d <- data.frame(cbind(cluster=1:2, value1=1:10, value2=11:20)) d FindClusterTraits <- function(framename, index){

Hi. I have a list where each object in the list has multiple parts. I'd like to take the mean of just one part of each object. Is it possible to do this with lapply? If not, can you recommend another function? Thanks. eric > x1 <- c(0,1,2,3) > x2 <- c(7,8) > x3 <- c(2,6,6,8) > x4 <- c(4,8) > > Lst1 <- list(label1 = x1,label2 = x2) > Lst2 <-

...undu) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Tue, 3 Apr 2007 11:58:27 +0200 > From: Adelchi Azzalini <azzalini at stat.unipd.it> > Subject: Re: [R] bivariate interpolation > To: "eric lee" <ericlee100 at gmail.com> > Cc: r-help at stat.math.ethz.ch > Message-ID: > <20070403115827.99d67de3.azzalini at stat.unipd.it> > Content-Type: text/plain; charset=ISO-8859-1 > > On Tue, 3 Apr 2007 11:43:55 +0200, Adelchi Azzalini > wrote: > > AA> On Mon, 2 Apr 2007 22:...

....html > and provide commented, minimal, self-contained, reproducible code. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? ------------------------------ Message: 17 Date: Mon, 29 Sep 2008 08:45:46 -0400 From: "eric lee" <ericlee100 at gmail.com> Subject: [R] adding labels to tapply results To: r-help at r-project.org Message-ID: <4056389d0809290545r592bfa5fl801b188a1d5b0b0a at mail.gmail.com> Content-Type: text/plain Hi, How do I get labels onto the output from tapply? I need the labels to merge the output with a...

Hi. I'm trying to take a data set with two independent and one dependent variable and enter a x,y value to predict the dependent with a nonparametric technique. I've been using interpp in the akima package, (windows xp, R 2.4.1), but get values that are orders of magnitude off when the predictors are slightly out of the range of the data set. Can you recommend a function for me?

Hi, I'm trying to use ad.test or ad2.test to test whether a given data set is exponential. I see that one of the function inputs is "distn", but I try "exponential" and 5 other variants, but I still get the error message: ad.test(test2, distn="exponential", fit=list(estimate = 0.167685), H=NA, sim=100) Error in ad.test(test2, distn = "exponential",

Hello, Can you tell me what R function to use to do a two-sample chi-squared test? I want to see if two distributions are significantly different from each other, and I don't specify the theoretical distribution of either. For example, I have the following fake count data: x <- sample(1:10,50,replace=TRUE) y <- sample(1:10,100,replace=TRUE) I saw chisq.test in the stats package, but

Hello, I'd like to pass a column name as the argument for a function, but I'm getting "NULL" as a return value. Any suggestions? Thanks. > d <- data.frame(cbind(x=1, y=1:10)) > d x y 1 1 1 2 1 2 3 1 3 4 1 4 5 1 5 6 1 6 7 1 7 8 1 8 9 1 9 10 1 10 > testing <- function(var) { + tst <- d$var[3] + tst + } > > dummy <- testing(y)

Hi, I'm running R 2.7.2 on windows XP. I'd like to find the maximum of a 3-d array over it's third index to create a 2-d array. For example: > x <- array(c(1,2,3,10,11,12,3:8),c(2,3,2)) > x , , 1 [,1] [,2] [,3] [1,] 1 3 11 [2,] 2 10 12 , , 2 [,1] [,2] [,3] [1,] 3 5 7 [2,] 4 6 8 > x1 <- x[,,1] > x2 <- x[,,2] >

Hello, I'm running R 2.7.2 in a windows XP environment and I run the following in an R console: library(ncdf) nc <-open.ncdf('c:/file.nc') aa <- get.var.ncdf(nc,'var1') This works fine, but 'aa' takes up about 100mb and I want to release the memory after using it. I try: rm(aa) close.ncdf(nc) and look at Windows Task Manager, but the memory hasn't been

Hi. I'm trying to run the elliptic package on my computer (windows platform, version 2.7.2). I downloaded the elliptic package zip file from http://lib.stat.cmu.edu/R/CRAN/ and installed it, but it says that it needs the "emulator" package. Can you tell me where to download this? The only similar package by name is 'emu_4.0.zip' which is not 'emulator.' I also

Hi, I'm trying to get the p-value from the 'lm' regression function as a list object. For example, I can get r^2 from the following code by entering summary(fm)$r.squared. Is there a way to get the p-value? If not, is there a function where I can enter the f-value and degrees of freedom to get the p-value? Thanks. x <- c(1,2,3,4,5,6,7,8,9,10) y <- c(1,2,3,4,4,5,6,8,1,9) fm