similar to: numerical subscripts in a loop in a plot

Hello, I was wondering if someone knows the formula used by the function lm to compute the t-values. I am trying to implement a linear regression myself. Assuming that I have K variables, and N observations, the formula I am using is: For the k-th variable, t-value= b_k/sigma_k With b_k is the coefficient for the k-th variable, and sigma_k =(t(x) x )^(-1) _kk is its standard deviation.

Dear list, I've tried several times to wrap my head around the Design library, without much success. It does some really nice things, but I'm often uncomfortable because I don't understand exactly what it's doing. Anyway, one thing I really like is the latex.ols() function, which converts an R linear model formula to a LaTeX equation. So, I started writing a latex.lm() function

I have data (each Y_i is a vector) in the form of Y_i = X_i \beta_i + Z_i b_i + epsilon_i Were it not for the measurement error (the epsilon_i) it's a very simple model --- nice and balanced, compound symmetry, and I'd just use lme(y ~ x1 + x2, random=~1|subj, ...) but the measurement error is throwing me off. Because the Y_i are actually derived from other data, I am able

type count 0 20 1 15 0 10 1 35 0 28 I would like to create two vectors from the data above. For example, type1=c(15, 35) and type0 = c(20, 10, 28). Can any one help Raphael

Hi! I was trying to install the RWinEdt library on a Windows Vista machine which had R 2.6.0, WinEdt 5.4 and the RWinEdt1.7.8.zip file in the library folder under the ...\R\2.6.0 directory. I am able to install fine form the local zip but I can't launch winedt from within R for some reason. > utils:::menuInstallLocal() package 'RWinEdt' successfully unpacked and MD5 sums checked

Hi I have data like 1, A, 24, The Red House 2, A, 25, King's Home, by the Sea ... I'd like to read this in as three variables. I first tried temp <-read.csv(addresses, sep = "," ) it worked but line 2 was broken after King's Home, and by the Sea as placed in another line. and so i eneded up with more number of rows than in the data. when i tried temp

Per the message from Alexander Nervedi, 29 April 2006: > I have to be making a riddiculously silly ommission. > when I run the fillowing i get the cloud plot ok. But I cant figure > out what I am missing out when I call wireframe. > Any help would be appreciated. > x<-runif(100) > y<-rnorm(100) > z<-runif(100) > temp <-data.frame(x,y,z) >

Dear All, I have a numerical problem: R, as other statistical software, can tell the difference between very small numbers and 0, while apparently cannot distinguish a number close to 1 and 1. In the example below, is it possible to instruct R to recognize that q is different from 1? > p=.00000000000000000000000000000001 > p==0 [1] FALSE > q=.99999999999999999999999999999 >

Hi R Gurus, I am trying to figure out what is going on here. > a <- 68.08 > b <- a-1.55 > a-b [1] 1.55 > a-b == 1.55 [1] FALSE > round(a-b,2) == 1.55 [1] TRUE > round(a-b,15) == 1.55 [1] FALSE Why should (a - b) == 1.55 fail when in fact b has been defined to be a - 1.55? Is this a precision issue? How do i correct this? Alex

Hi, suppose you have two versions of the same algorithm: one in pure R, the other one in C/C++ called via .Call(). Assuming there is no bug in the implementations (i.e. they both do the same thing), is there any well known reason why the C/C++ implementation could return numerical results non identical to the one obtained from the pure R code? (e.g. could it be rounding errors? please

I have the following csv file: name,x,y,z category,delta,gamma,epsilon a,1,2,3 b,4,5,6 c,7,8,9 I'd like to create a numeric matrix of just the numbers in this csv dataset. I've tried the following program: sample.data <- read.csv("sample.csv") numerical.data <- as.matrix(sample.data[-1,-1]) However, print(numerical.data) returns what appears to be a matrix of

Hi, To be able to match cases with a benchmark I need to have a data.frame with a character id variable. however, I am surprised why this seems to be so hard. In fact I was unable to succeed. Here is what I tried: >test1 <-expand.grid(ID = 1:2, sex = c("male","female")) >is(test1[,2]) [1] "factor" "oldClass" >test2 <-expand.grid(ID =

Dear list, When compiling the R-2.3.0 on FC4 x86_64, I got the following errors: make[3]: Entering directory `/project/scratch3/ligroup/wuming/src/R-2.3.0/src/main' gcc -Wl,--export-dynamic -L/usr/local/lib64 -o R.bin Rmain.o CConverters.o CommandLineArgs.o Rdynload.o Renviron.o RNG.o apply.o arithmetic.o apse.o array.o attrib.o base.o bind.o builtin.o character.o coerce.o colors.o complex.o

Dear All, I'm trying to save a dataframe using write.table command. It works, but when I retrieved, there's an error message as shown below: > write.table(soil.dat,file="C:/soil.rdata") > load("C:/soil.rdata") Error: bad restore file magic number (file may be corrupted)-- no data loaded I can figure out the error message. Any assistance to solve the

Dear RUsers, I just upgraded from 2.6.0 to 2.6.2 and tried to reinstall the RWinEdt patch to work with WinEdt so that I can continue function as I always have but I have run into problems that I don't understand how to fix. Any help would be great. Essentially, I downloaded the latest RWinEdt zip folder from the CRAN website and tried calling the library. I tried re-installing it a bunch of

Dear List: I'm working to construct a very large sparse matrix and have found relief using the SparseM package. I have encountered an issue that is confusing to me and wonder if anyone may be able to suggest a smarter solution. The matrix I'm creating is a covariance matrix for a larger research problem that is subsequently used in a simulation. Below is the latex form of the matrix if

Hi ! I have a shapefile that I can easily read into R using library(maptools). My problem stems from some warning messages that come even though everything seems to work fine. library(maptools) districts <- read.shape(filen = "a_ds", dbf.data = TRUE) length(districts$Shapes) so far so good. when I try and plot this I get a nice plot and a warning message: > plot(districts)

In e1071 package/svm default epsilon value is set to 0.1 and not 0.5 as documentation says. R

I have a project due in my Linear Regression class re: regression on a data set & my professor gave us a hint that there were *exactly *2 sig interactions. The data set is attached. We have to find which predictors are significant, & which 2 interactions are sig. Also, I nedd some guidance for this & selecting the best model. I tried the `full' model, that being:

Hi! Let's go back to this topic please! I have to replace the Windows NT 4.0 server with Samba but I still don't know how to do this. I need to allow to someone (some user group) the right to add files into the folder. They use this "feature" on current NT server ver often and to this in the following ways: 1. Rightclick on file you want to add, Copy, then go to server, for