similar to: analysis of categorical data

Displaying 20 results from an estimated 700 matches similar to: "analysis of categorical data"

2012 Sep 02
0
most efficient plyr solution
Dear list members, Any help on this efficiency issue would be greatly appreciated. I would like to find the most efficient way to run a non-vectorized function (here: fisher exact test p-value) iteratively using 4 matrices with identical dimensions. And as a result I aim for an array with identical dimensions containing the corresponding p-values. Please consider some code using a trivial
2010 Dec 15
3
Applying function to a TABLE and also "apply, tapply, sapply etc"
Dear R-help forum members, Suppose I have a data-frame having two variables and single data for each of them, as described below. variable_1           variable_2         10                          20 I have written a function, say, 'fun' which uses input 10 and 20 and gives me desired result. fun = function(X, Y)          {          X + Y              #( I am just giving an example of
2011 Dec 12
1
Detecting typo in function argument
With some chagrin after spending a couple of hours trying to debug a script, I realized I had typed in something like ans<-optimx(start, myfn, mygr, lower<-lo, upper=up) that is, the "<-" rather than "=". The outcome on my machine was a non-obvious error several layers deep in the call stack. For info, optim() seems to stop much more quickly. The error is
2006 Mar 09
0
When calling external C-function repeatedly I get different results; can't figure out why..
Dear all, I need to calculate tr(xyxy) fast for matrices x and y. Inspired by the R-source code, I've created the following functions (I am *new* to writing external C-functions, so feel free to laugh at my code - or, perhaps, suggest changes): #include <Rinternals.h> #include <R_ext/Applic.h> /* for dgemm */ static void matprod(double *x, int nrx, int ncx, double *y, int
2006 Mar 09
0
When calling external C-function repeatedly I get differentresults; can't figure out why..
Not an expert in programming either, but to me it seems like you've forgotten to initialize the variable "tr". It just picks up garbage from allocated memory previously initialized by other processes. Med venlig hilsen Frede Aakmann T?gersen > -----Oprindelig meddelelse----- > Fra: r-help-bounces at stat.math.ethz.ch > [mailto:r-help-bounces at stat.math.ethz.ch] P?
2004 Jul 03
4
counting the occurrences of vectors
Hi: I have two matrices, A and B, where A is n x k, and B is m x k, where n >> m >> k. Is there a computationally fast way to count the number of times each row (a k-vector) of B occurs in A? Thanks for any suggestions. Best, Ravi. [[alternative HTML version deleted]]
2008 May 16
3
radio button observe field only triggers once
Hi, If i add field observers to radio button fields they trigger once but then nothing after that. I have multiple fields in a form that i need to know if one of them changes and which spedific field. Below is an example of two foelds i tested and they trigger once with the alert but then nothing after that. I also tried individual observers for each field test_yes and test_no but with the same
2007 Jul 19
0
a type of generalized inner product
Hi. I'm looking for an efficient way of writing a function(x,mat1,mat2). n<-4 m<-4 r<-3 x <- array(sample(1:1000)/10^4,rep.int(n,m)) mat1 <- matrix(sample(1:1000)/10^4,n,n) mat2 <- matrix(sample(1:1000)/10^4,n,n) It needs to work for *any* itegers n, r<=m with output (in horrible gory detail) equivalent to: ans<-array(0,rep.int(n,(m+1))) for(i1 in 1:n) for(i2 in
2012 Aug 04
3
Head or Tails game
Hi, Reading about a "Heads and Tails" game in http://www.dartmouth.edu/~chance/teaching_aids/books_articles/probability_book/amsbook.mac.pdf Introduction to Probability (Example 1.4, pp. 5-8). You toss a coin 40 times. If heads, Peter wins $1, tails, he loses $1. I think I can do that ok with: winnings <- sum(sample(c(-1,1), 40, replace=TRUE)) But I have to do it 10,000 times
2010 Jun 29
1
Performance enhancement for ave
library(plyr) n<-100000 grp1<-sample(1:750, n, replace=T) grp2<-sample(1:750, n, replace=T) d<-data.frame(x=rnorm(n), y=rnorm(n), grp1=grp1, grp2=grp2) system.time({ d$avx1 <- ave(d$x, list(d$grp1, d$grp2)) d$avy1 <- ave(d$y, list(d$grp1, d$grp2)) }) # user system elapsed # 39.300 0.279 40.809 system.time({ d$avx2 <- ave(d$x, interaction(d$grp1, d$grp2, drop =
2013 Feb 14
0
Building a Package & using gWidgets
Hi, For the past few months I've been building a simulation in R I hope to package. It consists of two usable functions, and many internal ones which one of the two usable functions call while looping, to perform the stages of simulation. A simple conceptual example is: # Abstract representation 1st Usable function, generates object containing settings for simulation. settings <-
2004 Jul 01
3
list structure question
Hi, I have a list in which element is a vector (all of the same length and all numeric). I want to find the mean of the first elements of the vectors, the mean of the second elements of the vectors and so on. Currently I convert the list to a data.frame and apply rowMeans(). But is there a way to to do this directly on the list? I seem to recall a post in which there was such a function (or
2008 Aug 27
5
Integrate a 1-variable function with 1 parameter (Jose L. Romero)
Hey fellas: I would like to integrate the following function: integrand <- function (x,t) { exp(-2*t)*(2*t)^x/(10*factorial(x)) } with respect to the t variable, from 0 to 10. The variable x here works as a parameter: I would like to integrate the said function for each value of x in 0,1,..,44. I have tried Vectorize to no avail. Thanks in advance, jose romero
2004 Dec 16
8
counting numbers without replicates in a vector
Hi, I am just wondering if there is an easy way to count in a numeric vector how many numbers don't have replicates. For example, a=c(1,1,2,2,3,4,5), how can I know there are three numbers (3, 4 and 5) without replicates? Thank you! Jun =====
2006 Dec 05
4
has_many with :uniq not working for me
Hi all, I have a relationship (no really!) class RiskMatrix < ActiveRecord::Base has_many :severities, :order => :position, :uniq => true end class RiskFactor < ActiveRecord::Base belongs_to :risk_matrix validates_presence_of :descriptor, :example validates_uniqueness_of :descriptor, :example, :scope=> :risk_matrix_id end class Severity < RiskFactor
2010 Sep 17
0
question on OPTIMX with installing and using
Dear R users I have tried to install the optimx but met problems. I have gone to the website you suggested: https://r-forge.r-project.org/R/?group_id=395 and tried to install it with the following method: install.packages("optimx", repos="http://R-Forge.R-project.org") I have received the following information: package 'numDeriv' successfully unpacked and MD5
2007 Feb 08
2
Timings of function execution in R [was Re: R in Industry]
On 2/8/07, Albrecht, Dr. Stefan (AZ Private Equity Partner) <stefan.albrecht at apep.com> wrote: > Dear all, > > Thanks a lot for your comments. > > I very well agree with you that writing efficient code is about optimisation. The most important rules I know would be: > - vectorization > - pre-definition of vectors, etc. > - use matrix instead of data.frame > - do
2012 Jul 22
4
pvalue calculate
I have a value a=300 observation (x) = sample(1:50) How to find a p-value from this. I need to show that "a" is different fom mean(x). Thanks -- ------------- Mary Kindall Yorktown Heights, NY USA [[alternative HTML version deleted]]
2009 Dec 08
4
lower.tail option in pnorm
Hi, I would have thought that these two constructions would produce the same result but they do not. Resp <- rbinom(10, 1, 0.5) Stim <- rep(0:1, 5) mm <- model.matrix(~ Stim) Xb <- mm %*% c(0, 1) ifelse(Resp, log(pnorm(Xb)), log(1 - pnorm(Xb))) pnorm(as.vector(Xb), lower.tail = Resp, log.p = TRUE) > ifelse(Resp, log(pnorm(Xb)), log(1 - pnorm(Xb))) [1] -0.6931472 -1.8410216
2011 Sep 02
5
Hessian Matrix Issue
Dear All, I am running a simulation to obtain coverage probability of Wald type confidence intervals for my parameter d in a function of two parameters (mu,d). I am optimizing it using "optim" method "L-BFGS-B" to obtain MLE. As, I want to invert the Hessian matrix to get Standard errors of the two parameter estimates. However, my Hessian matrix at times becomes