Displaying 20 results from an estimated 2000 matches similar to: "Function to compute the multinomial beta function?"
2009 Oct 24
2
Implementation of gamma function for large number
Hi - I ran into a problem when the argument to gamma function is
large. Says, if I do the following:
> gamma(17000)
[1] Inf
Warning message:
value out of range in 'gammafn'
Is there anyway to get around this or other implementation? Thank you.
-rc
2012 Aug 01
3
Neuralnet Error
I require some help in debugging this code
library(neuralnet)
ir<-read.table(file="iris_data.txt",header=TRUE,row.names=NULL)
ir1 <- data.frame(ir[1:100,2:6])
ir2 <- data.frame(ifelse(ir1$Species=="setosa",1,ifelse(ir1$Species=="versicolor",0,"")))
colnames(ir2)<-("Output")
ir3 <- data.frame(rbind(ir1[1:4],ir2))
2012 Oct 05
2
problem with convergence in mle2/optim function
Hello R Help,
I am trying solve an MLE convergence problem: I would like to estimate
four parameters, p1, p2, mu1, mu2, which relate to the probabilities,
P1, P2, P3, of a multinomial (trinomial) distribution. I am using the
mle2() function and feeding it a time series dataset composed of four
columns: time point, number of successes in category 1, number of
successes in category 2, and
2008 Jun 30
3
Is there a good package for multiple imputation of missing values in R?
I'm looking for a package that has a start-of-the-art method of
imputation of missing values in a data frame with both continuous and
factor columns.
I've found transcan() in 'Hmisc', which appears to be possibly suited
to my needs, but I haven't been able to figure out how to get a new
data frame with the imputed values replaced (I don't have Herrell's book).
Any
2011 Jun 05
3
How to convert a factor column into a numeric one?
I have a data frame:
> head(df)
Time Temp Conc Repl Log10
1 0 -20 H 1 6.406547
2 2 -20 H 1 5.738683
3 7 -20 H 1 5.796394
4 14 -20 H 1 4.413691
5 0 4 H 1 6.406547
7 7 4 H 1 5.705433
> str(df)
'data.frame': 177 obs. of 5 variables:
$ Time : Factor w/ 4 levels
2007 May 03
4
Survival statistics--displaying multiple plots
Hello all!
I am once again analyzing patient survival data with chronic liver disease.
The severity of the liver disease is given by a number which is continuously
variable. I have referred to this number as "meld"--model for end stage
liver disease--which is the result of a mathematical calculation on
underlying laboratory values. So, for example, I can generate a Kaplan-Meier
plot
2013 May 12
1
Multinomial-Dirichlet using R
Hi:
I have asked this question on Cross-Validated. So it might be a cross
posting but havent received any responses to it.
I am trying to see which distribution will best fit the data I am working
on. The dataset is as following:
Site Nausea headache Abdominal Distension
1 17 5 10
2 12
2003 Jan 22
1
negative multinomial regression models
Hello,
I''ve spent a lot of time during the past month trying to get negative
multinomial regression models for clustered event counts as described in
(Guang Guo. 1996. "Negative Multinomial Regression Models For Clustered
Event Counts." Sociological Methodology 26: 113-132., abstract at
http://depts.washington.edu/socmeth2/4abst96.htm) implemented in R. A
FORTRAN version of the
2008 Apr 22
2
Multidimensional contingency tables
How does one ideally handle and display multidimenstional contingency
tables in R v. 2.6.2?
E.g.:
> prob1<- data.frame(victim=c(rep('white',4),rep('black',4)),
+ perp=c(rep('white',2),rep('black',2),rep('white',2),rep('black',2)),
+ death=rep(c('yes','no'),4), count=c(19,132,11,52,0,9,6,97))
> prob1
victim perp
2011 Feb 09
2
comparing proportions
Hi, I have a dataset that has 2 groups of samples. For each sample, then
response measured is the number of success (no.success) obatined with the number
of trials (no.trials). So a porportion of success (prpop.success) can be
computed as no.success/no.trials. Now the objective is to test if there is a
statistical significant difference in the proportion of success between the 2
groups of
2007 Sep 10
1
S-Plus "resample" package and associated functions
Are there any packages in R that reproduce the package "resample" of S-Plus?
The sample() function in R doesn't provide equivalent flexibility of
bootstrap() and bootstrap2().
================================================================
Robert A. LaBudde, PhD, PAS, Dpl. ACAFS e-mail: ral at lcfltd.com
Least Cost Formulations, Ltd. URL: http://lcfltd.com/
824
2008 Sep 25
1
R function which finds confidence interval for binomial variance
I need to construct confidence intervals for the binomial variance.
This is the usual estimate
v = x*(n-x)/n
or its unbiased counterpart
v' = x*(n-x)/(n-1)
where x = binomial number of successes observed in n Bernoulli trials
from proportion p.
The usual X^2 method for variance confidence intervals will not work,
because of the strong non-normal character of the sampling
2010 Jun 21
2
Singularity in simple ANCOVA problem
I'm using R 2.10.1 with the latest version of all packages (updated today).
I'm confused as to why I'm getting a hard singularity in a simple set
of experimental data:
> blots
ID Lot Age Conc
1 1 A 3 4.44
2 2 A 3 4.56
3 3 B 41 4.03
4 4 B 41 4.57
5 5 C 229 4.49
6 6 C 229 4.66
7 7 D 238 3.88
8 8 D 238 3.93
9 9 E 349 4.43
10 10 E 349
2010 Dec 09
1
Constraints when sampling from a distribution
Dear R-helpers,
My question is related to how to impose constraints when when sampling from a distribution.
For example, suppose I'm sampling a vector from a multivariate normal distribution
vbeta <- 100*diag(2)
mbeta <- c(1,1)
ans <- beta <- c(rmvnorm(1,mbeta,vbeta))
ans will thus be a vector with two elements.
My question is how do I place a restriction on one of the
2009 Sep 03
1
Problem accessing functions in package 'roxygen'
I have Vista Home with R-2.9.0, and installed and tried to test the
package 'roxygen':
> utils:::menuInstallPkgs()
trying URL
'http://lib.stat.cmu.edu/R/CRAN/bin/windows/contrib/2.9/roxygen_0.1.zip'
Content type 'application/zip' length 699474 bytes (683 Kb)
opened URL
downloaded 683 Kb
package 'roxygen' successfully unpacked and MD5 sums checked
The
2008 Jul 12
5
shapiro wilk normality test
Hi everybody,
somehow i dont get the shapiro wilk test for normality. i just can?t
find what the H0 is .
i tried :
shapiro.test(rnorm(5000))
Shapiro-Wilk normality test
data: rnorm(5000)
W = 0.9997, p-value = 0.6205
If normality is the H0, the test says it?s probably not normal, doesn
?t it ?
5000 is the biggest n allowed by the test...
are there any other test ? ( i know qqnorm
2008 Apr 10
1
Problem installing and using package "tseries"
I have R 2.6.2, and have tried downloading and installing the package
"tseries". I get the same error when I use two different mirror sites:
> utils:::menuInstallPkgs()
trying URL
'http://cran.mirrors.hoobly.com/bin/windows/contrib/2.6/tseries_0.10-14.zip'
Content type 'application/zip' length 400799 bytes (391 Kb)
opened URL
downloaded 391 Kb
package
2008 Aug 25
1
Specifying random effects distribution in glmer()
I'm trying to figure out how to carry out a Poisson regression fit to
longitudinal data with a gamma distribution with unknown shape and
scale parameters.
I've tried the 'lmer4' package's glmer() function, which fits the
Poisson regression using:
library('lme4')
fit5<- glmer(seizures ~ time + progabide + timeXprog +
offset(lnPeriod) + (1|id),
data=pdata,
2007 Jun 10
1
Windows vista's early terminate Rgui execution
Hi,I have a frustrating problem from vista that I wonder if anyone has come across the same problem. I wrote a script that involves long computational time (although, during the calculation, it spits out text on the gui to notify me the progress of the calculation periodically). Windows vista always stopped my calculation and claimed that 'Rgui is stop-working. Windows is checking for
2007 Jun 19
1
Iterative Solver [Converting Matlab's solve()]
I can't for the life of me figure out how to get the roots for this simple
(but sovable only iteratively) equation in R:
x = z*(1-(1-2/z)^y
where x and y are known, and z is unknown. In Matlab, this amounts to:
[my.solution] = solve('x = z*(1-(1-2/z)^y')
my.solution.real = solution(y-1,y)
% bottom line displays non-imaginary solution (last element)
Obviously, I'm deeply