similar to: R accuracy

Displaying 20 results from an estimated 400 matches similar to: "R accuracy"

2006 Jul 14
2
References verifying accuracy of R for basic statisticalcalculations and tests
Hi, > [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Corey Powell > > Do you know of any references that verify the accuracy of R > for basic statistical calculations and tests. The results of > these studies should indicate that R results are the same as > the results of other statistical packages to a certain number > of decimal places on some benchmark
2005 Jun 27
2
Numerical accuracy
Hi people, I need to prove the good quality of numerical accuracy of R. Anyone knows a paper or anything else comparing R to other statistical softwares in terms of numerical accuracy. I've made a long search about that but I found nothing. Please help me!! Thanx, Talita Leite ------------------------------------------------- Este e-mail foi enviado pelo Webmail da UFAL IMP:
2005 Mar 18
1
Pb with ks.test pvalue
Hello, While doing test of normality under R and SAS, in order to prove the efficiency of R to my company, I notice that Anderson Darling, Cramer Van Mises and Shapiro-Wilk tests results are quite the same under the two environnements, but the Kolmogorov-smirnov p-value really is different. Here is what I do: > ks.test(w,pnorm,mean(w),sd(w)) One-sample Kolmogorov-Smirnov test data: w D
2005 Apr 06
1
nls.control
Hello everyone, I'm trying to test the accurracy of R on the Eckerle4 dataset from NIST and I don't understand how the control option of the nls function works. I tought nls(...) was equivalent to nls(...control=nls.control()) i.e nls.control() was the default value of control, but here is the error I get : > n2=nls(V1~(b1/b2) *
2006 Jul 30
2
NIST StRD linear regression
NIST maintains a repository of Statistical Reference Datasets at http://www.itl.nist.gov/div898/strd/. I have been working through the datasets to compare R's results to their references with the hope that if all works well, this could become a validation package. All the linear regression datasets give results with some degree of accuracy except one. The NIST model includes 11 parameters,
2012 May 04
3
read-in, error???
Dear Users! I encountered with some problem in data reading while I challenged R (and me too) in a validation point of view. In this issue, I tried to utilize some reference datasets ( http://www.itl.nist.gov/div898/strd/index.html). And the result departed a bit from my expectations. This dataset dedicated to challenge cancellation and accumulation errors (case SmLs07), that's why this
2004 Apr 02
3
Single Factor Anova
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello all - As I progress in R I am trying to automate functions I would have normally farmed out to Excel, SPSS or Statistica. Single factor anova is one of them. For example, a dataset from NIST StRD (http://www.itl.nist.gov/div898/strd/anova/AtmWtAg.html) has two groups: 1 2 107.8681568 107.8681079 107.8681465 107.8681344
2012 May 11
0
NLS sensitivity to start= values or poles in data range
Greetings R-help! I'm fairly new to R and am trying to expand my knowledge beyond using R for simple summary statistics and basic tests. To that end I am attempting to write an interactive R-script that will perform a general rational function fit to a given dataset based on the example given at http://www.itl.nist.gov/div898/handbook/pmd/section6/pmd64.htm. The problem that I seem to have
2003 Sep 04
0
SUMMARY: Comparison of SAS & R/Splus
My thanks to Drs. Armstrong, Bates, Harrell, Liaw, Lumley, Prager, Schwartz, and Mr. Wang for their replies. I have pasted my original message and their replies below. After viewing http://www.itl.nist.gov/div898/strd/ as suggested by Dr. Schwartz, it occurred to me that it might be educational to search for some data repositories on google. I was able to find some,though I'm sure many of
2008 May 29
3
Datasets in R
I?m trying to find datasets that will give me residuals, after applying the lm function, with no normality, non linearity, and heteroscedacity so I can try to exemplify those cases in the linear regression model. Can you give any advice on what datasets would be appropiate? I can?t use the ones in the alr3 package because those have already been seen in class. Thank you very much :-) natorro
2001 Jan 10
2
Levenberg-Marquardt algorithm
Hi All, Is the Levenberg-Marquardt algorithm available in R. This method combines the steepest descent algorithm and Newton's method. Thanks in Advance, Dermot MacSweeney. ************************************************************** Dermot MacSweeney NMRC, Email: dsweeney at nmrc.ucc.ie Lee Maltings, Tel: +353 21 904178 Prospect Row, Fax: +353 21 270271 Cork, WWW:
2011 Oct 23
0
FW: Re: symmetric matrix multiplication
Just to avoid possible confusion, let me correct a typo (at step [2] in the example below). Apologies! -----FW: <XFMail.111023084327.ted.harding at wlandres.net>----- Date: Sun, 23 Oct 2011 08:43:27 +0100 (BST) Sender: r-help-bounces at r-project.org From: (Ted Harding) <ted.harding at wlandres.net> To: r-help at r-project.org Subject: Re: [R] symmetric matrix multiplication On
2013 Feb 20
3
NLS results different from Excel -- Tricky fortunes nomination
Folks: I thought the following excerpt from Bruce McCullough's post would be a good candidate for the R fortunes package -- except that it's about Excel, not R! So I nominate it... but leave it to others to say whether it's really "qualified" to be nominated. ---- "The idea that the Excel solver "has a good reputation for being fast and accurate" does not
2013 Feb 20
1
NLS results different from Excel
The idea that the Excel solver "has a good reputation for being fast and accurate" does not withstand an examination of the Excel solver's ability to solve the StRD nls test problems. Solver's ability is abysmal. 13 of 27 "answers" have zero accurate digits, and three more have fewer than two accurate digits -- and this is after tuning the solver to get a good
2012 Jan 23
2
[LLVMdev] Use of 'ldrd' instructions with unaligned addresses on armv7 (Major bug in LLVM optimizer?)
Hi, I think I discovered a major armv7 optimization bug in Clang. I create a simple test case which exhibits the issue. When you compile the attached file for armv7 with optimizations turned on (O2, O3 or Os), the binary generated led to a crash. The issue can't be reproduced when using GCC 4.2. It can't be reproduced with Clang when the optimization is turned off (O0). This issue can be
2007 Jul 04
2
probabilty plot
Hi all, I am a freshman of R,but I am interested in it! Those days,I am learning pages on NIST,with url http://www.itl.nist.gov/div898/handbook/eda/section3/probplot.htm, I am meeting a problem about probability plot and I don't know how to plot a data set with R. Could somebody tell me the answer,and a example is the best! I will look forward to your answer. Thank you very much.
2012 Jun 25
2
Fractional Factorial - Wrong values using lm-function
Hello. I'm a new user of R, and I have a question regarding the use of aov and lm-functions. I'm doing a fractional factorial experiment at our production site, and I need to familiarize myself with the analysis before I conduct the experiment. I've been working my way through the examples provided at http://www.itl.nist.gov/div898/handbook/pri/section4/pri472.htm
2012 Jan 23
0
[LLVMdev] Use of 'ldrd' instructions with unaligned addresses on armv7 (Major bug in LLVM optimizer?)
The problem is in your code, not the compiler. You're casting an unaligned char* to an int*, even though an int* pointer must be 4-byte aligned in every ARM ABI that I've ever seen. On Jan 23, 2012, at 6:14 AM, Alexandre Colucci wrote: > Hi, > > I think I discovered a major armv7 optimization bug in Clang. I create a simple test case which exhibits the issue. > When you
2013 Oct 08
1
how to check the accuracy for maxent ?
I was going through this example of maxent use: http://cran.r-project.org/web/packages/maxent/maxent.pdf # LOAD LIBRARY library(maxent) # READ THE DATA, PREPARE THE CORPUS, and CREATE THE MATRIX data <- read.csv(system.file("data/NYTimes.csv.gz",package="maxent")) corpus <- Corpus(VectorSource(data$Title[1:150])) matrix <- DocumentTermMatrix(corpus) # TRAIN/PREDICT
2012 Sep 13
1
Package for comparing sensitivity, specificity, PPV, NPV, and accuracy?
Hi, I have two sets of sensitivity, specificity, positive predictive value, and negative predictive value, and accuracy from two tests on the same subjects. Is there an R package that does such paired comparisons? Thanks, Gang Chen