Displaying 20 results from an estimated 1000 matches similar to: "Batch file export"
2008 May 04
1
Is my understanding of rlnorm correct?
rlnorm takes two 'shaping' parameters: meanlog and sdlog.
meanlog would appear from the documentation to be the log of the mean.
eg if the desired mean is 1 then meanlog=0.
So to generate random values that fit a lognormal distribution I would
do this:
rlnorm(N , meanlog = log(mean) , sdlog = log(sd))
But when I check the mean I don't get it when sdlog>0. Interestingly I
2004 May 01
2
Generating Lognormal Random variables (PR#6843)
Full_Name: Anthony Gichangi
Version: 1.90
OS: Windows XP Pro
Submission from: (NULL) (130.225.131.206)
The function rlnorm generates negative values for lognormal distribution.
x- rlnorm(1000, meanlog = 0.6931472, sdlog = 1)
Regards
Anthony
2013 May 10
1
rlnorm(n, meanlog = 0, sdlog = 1)
Hi list,
Does anyone know the code behind rlnorm(n, meanlog = 0, sdlog = 1)? I am
going to write it in c#.
thanks
Alireza
[[alternative HTML version deleted]]
2005 Jun 29
2
MLE with optim
Hello,
I tried to fit a lognormal distribution by using optim. But sadly the output
seems to be incorrect.
Who can tell me where the "bug" is?
test = rlnorm(100,5,3)
logL = function(parm, x,...) -sum(log(dlnorm(x,parm,...)))
start = list(meanlog=5, sdlog=3)
optim(start,logL,x=test)$par
Carsten.
[[alternative HTML version deleted]]
2009 May 31
1
Bug in truncgof package?
Dear R-helpers,
I was testing the truncgof CRAN package, found something that looked
like a bug, and did my job: contacted the maintainer. But he did not
reply, so I am resending my query here.
I installed package truncgof and run the example for function ad.test. I
got the following output:
set.seed(123)
treshold <- 10
xc <- rlnorm(100, 2, 2) # complete sample
xt <- xc[xc >=
2002 Dec 10
1
Lognormal distribution
I am trying to fit a lognormal distribution to a set of data and test its
goodness of fit with regard to predicted values.
I managed to get so far:
> y <- c(2,6,2,3,6,7,6,10,11,6,12,9,15,11,15,8,9,12,6,5)
> library(MASS)
> fitdistr(y,"lognormal",start=list(meanlog=0.1,sdlog=0.1))
meanlog sdlog
1.94810515 0.57091032
(0.12765945) (0.09034437)
But I would
2003 Aug 28
2
ks.test()
Dear All
I am trying to replicate a numerical application (not computed on R) from an
article. Using, ks.test() I computed the exact D value shown in the article
but the p-values I obtain are quite different from the one shown in the
article.
The tests are performed on a sample of 37 values (please see "[0] DATA"
below) for truncated Exponential, Pareto and truncated LogNormal
2014 Oct 15
2
Test K-S con distribuciones LogNormales
Hola Ruben,
Sí precisamente es lo que comentas, en matemáticas no se suele llamar
bucketización (este término se emplea más en informática) sino datos
agrupados. Pero la idea es la que tu mismo dices.
Respecto a las gráficas que has puesto, me han aclarado mucho sobre el
tema, gracias.
Si realizo lo mismo, por ejemplo con nbucket=1000 sigo obteniendo un
p-valor de 1. Es decir, que casi le
2007 Oct 03
1
offset in survreg
Hello,
I have a question regarding the use of an offset term with survreg(),
in the Survival library. In particular, I am trying to figure out on
what scale the offset term should be.
Here's a simple example with no censoring and no coefficients:
---------
y = rlnorm(1000, meanlog = 10, sdlog = 2)
delta = rep(1, 1000)
int = rep(1, 1000)
survreg(Surv(y,delta)~offset(10*int), dist =
2005 Jan 07
3
lognorm
Hi!
I 've a problem to have a lognorm distribution with
mean=1 and var (or sigma)=1.
rlnorm(1000,0,0)
rlnorm(1000,1,1)
rlnorm(1000,0,1)
.... ?
Can you help me?
2003 Jul 25
5
named list 'start' in fitdistr
Hi R lovers!
I'd like to know how to use the parameter 'start' in the function
fitdistr()
obviously I have to provide the initial value of the parameter to optimize
except in the case of a certain set of given distribution
Indeed according to the help file for fitdistr
" For the following named distributions, reasonable starting values
will be computed if `start'
2009 Feb 11
3
Generating Numbers With Certain Distribution in R
Dear all,
Is there a way to generate K numbers of integer (K = 10^6).
The maximum value of the integer is 200,000 and minimum is 1.
And the occurrences of this integer follows
a lognormal distribution.
- Gundala Viswanath
Jakarta - Indonesia
2002 Jul 12
1
Minor bug in dlnorm (PR#1781)
The density of a lognormal should be 0 for negative arguments, but
> dlnorm(-1)
[1] NaN
Warning message:
NaNs produced in: dlnorm(x, meanlog, sdlog, log)
A simple fix is to change dlnorm's definition to:
function (x, meanlog = 0, sdlog = 1, log = FALSE)
.Internal(dlnorm(x*(x>0), meanlog, sdlog, log))
It might be faster to put the same sort of adjustment into the
internal code, but
2012 Oct 14
0
multivariate lognormal distribution simulation in compositions
Dear All,
thanks to Berend, my question posted yesturday was solved succesfully here: http://r.789695.n4.nabble.com/hep-on-arithmetic-covariance-conversion-to-log-covariance-td4646068.html . I posted the question with the assumption of using the results with rlnorm.rplus() from compositions. Unfortunatelly, I am not getting reasonable enough outcome. Am I applying the results wrongfully? The
2012 Jun 03
0
Bug in truncgof package?
Dear Carlos, Duncan and everyone
You may have already sorted the matter by now, but since I have not seen
anything posted since Duncan's reply, here I go. I apologize in advance
for the spam, if it turns out I've missed some post.
I think the test and the implementation of the truncgof package are just
fine. I've done Carlos' experiment (repeatedly generating samples and
testing
2011 Jan 02
1
How to compute the density of a variable that follows a proportional error distribution
Hello,
I am trying to compute the density of a variable k that is either (1)
Normally distributed; (2) Log-Normally distributed; or (3) follows
proportional error distribution. I tried to search R-help and the answer for
normal distribution was easy to find (please see 1c). I am not sure if my
formula for dlnorm is correct (please see 2c below)? I really don't know
what function to use for the
2009 Aug 07
0
Fitting Truncated Distribution
Dear All,
I know that this topic has been already discussed on this list (see e.g.
http://markmail.org/message/bq2bdxwblwl4rpgf?q=r+fit+truncated+lognormal&page=1&refer=2ufc4fb2eftfwwml#query:r%20fit%20truncated%20lognormal+page:1+mid:7wxgkdxhixotorr5+state:results
for the case of weibull distribution), but I am experiencing some problems.
I deal with truncated distributions (that this to
2011 Jun 07
1
R results explanation
Hi all,
this might be a stupid question, but still.
Everytime i find some new function it's prettty easy to understand how to
use the syntax and to perform a text. Even the general idea of what the
function does is pretty easy to understand, but i can not find an
explanation (detailed explanation) of the R output for each function. For
example, a function fitdistr() in MASS package i
2000 Apr 04
1
Question about the proper use of outer()
DeaR all,
I do not have a clue with is the following NOT working like I expect to
do...
(and I cannot find any answer at CRAN)...
# This one is for my sample
> x _ seq(3,10)
# This two for parameters
> a _ seq(2,4)
> b _ seq(2,5)
# This one for the likelihood of a sample
>f _ function(a,b) {
+ prod(dlnorm(x,meanlog=a,sdlog=b))
+ }
> outer(a,b,f)
[,1] [,2]
2011 Jul 30
2
NAN problem
Hi All,
Did anyone else have a problem like this? I am sorry if its a small issue, I
seem to not understand what to do to get rid of this error.
> Sigma
[1] 0.1939025
> MuRest
[1] 8.512772
> TauZero
[1] 0.1
> curve(qlnorm(x,-TauZero+MuRest, Sigma,lower.tail=F), xlim=c(4000,9000),
ylim=c(0,.99),xlab="", ylab="")
Warning message:
In qlnorm(p, meanlog, sdlog,