Displaying 20 results from an estimated 1000 matches similar to: "How does this function print, why is n1 which equals 1 printed as 2?"
2008 Feb 15
1
Questions about EM algorithm
Dear all:
Assume I have 3 distributions, x1, x2, and x3.
x1 ~ normal(mu1, sd1)
x2 ~ normal(mu2, sd2)
x3 ~ normal(mu3, sd3)
y1 = x1 + x2
y2 = x1 + x3
Now that the data I can observed is only y1 and y2. It is
easy to estimate (mu1+m2), (mu1+mu3), (sd1^2+sd2^2) and
(sd1^2+sd3^2) by EM algorithm since
y1 ~ normal(mu1+mu2, sqrt(sd1^2+sd2^2)) and
y2 ~ normal(mu1+mu3, sqrt(sd1^2+sd3^2))
However, I want
2010 Jul 18
2
loop troubles
Hi all, I appreciate the help this list has given me before. I have a
question which has been perplexing me. I have been working on doing a
Bayesian calculating inserting studies sequentially after using a
non-informative prior to get a meta-analysis type result. I created a
function using three iterations of this, my code is below. I insert prior
mean and precision (I add precision manually
2004 Sep 16
3
Estimating parameters for a bimodal distribution
For several years, I have been using Splus to analyze an ongoing series of
datasets that have a bimodal distribution. I have used the following
functions, in particular the ms() function, to estimate the parameters: two
means, two standard deviations, and one proportion. Here is the code I've
been using in S:
btmp.bi <- function(vec, p, m1, m2, sd1, sd2)
{
2009 Jun 08
1
Interpreting R -results for Bivariate Normal
HI Guys,
I know that this forum is not for homework but I am trying to interpret R
output code.
I was just wondering if someone might be able to help.
I have been given the following.
For (X1,X2) distributed bivariate normal with parameters
mu1 = 5.8
mu2 = 5.3
sd1 = sd2 = 0.2
and p = 0.6
The r-code and inpit/output are as follows
input
m <- 5.3 + 0.6*(6.3 - 5.8)
s <-
2005 Jan 08
2
Does R accumulate memory
Dear List:
I am running into a memory issue that I haven't noticed before. I am
running a simulation with all of the code used below. I have increased
my memory to 712mb and have a total of 1 gb on my machine.
What appears to be happening is I run a simulation where I create 1,000
datasets with a sample size of 100. I then run each dataset through a
gls and obtain some estimates.
This works
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
2007 Oct 23
1
How to avoid the NaN errors in dnbinom?
Hi, The code below is giving me this error message:
Error in while (err > eps) { : missing value where TRUE/FALSE needed
In addition: Warning messages:
1: In dnbinom(x, size, prob, log) : NaNs produced
2: In dnbinom(x, size, prob, log) : NaNs produced
I know from the help files that for dnbinom "Invalid size or prob will
result in return value NaN, with a warning", but I am not able
2006 May 21
2
nls & fitting
Dear All,
I may look ridiculous, but I am puzzled at the behavior of the nls with
a fitting I am currently dealing with.
My data are:
x N
1 346.4102 145.428256
2 447.2136 169.530634
3 570.0877 144.081627
4 721.1103 106.363316
5 894.4272 130.390552
6 1264.9111 36.727069
7 1788.8544 52.848587
8 2449.4897 25.128742
9 3464.1016 7.531766
10 4472.1360 8.827367
11
2005 Nov 09
2
About: Error in FUN(X[[1]], ...) : symbol print-name too long
Hi,
I??m trying to use the Win2BUGS package from R and I have a similar problem
that reurns with the message:
Error in FUN(X[[1]], ...) : symbol print-name too long
But, there is no stray ` character in the file ( Sugestions given by: Duncan
Temple Lang <duncan>
Date: Mon, 26 Sep 2005 07:31:08 -0700 )
The progam in R is:
library(R2WinBUGS)
library(rbugs)
dat <-
2007 Mar 06
2
Estimating parameters of 2 phase Coxian using optim
Hi,
My name is Laura. I'm a PhD student at Queen's University Belfast and have
just started learning R. I was wondering if somebody could help me to see
where I am going wrong in my code for estimating the parameters [mu1, mu2,
lambda1] of a 2-phase Coxian Distribution.
cox2.lik<-function(theta, y){
mu1<-theta[1]
mu2<-theta[2]
lambda1<-theta[3]
2010 May 18
25
Very serious performance degradation
Hi,
I''m running Opensolaris 2009.06, and I''m facing a serious performance loss with ZFS ! It''s a raidz1 pool, made of 4 x 1TB SATA disks :
zfs_raid ONLINE 0 0 0
raidz1 ONLINE 0 0 0
c7t2d0 ONLINE 0 0 0
c7t3d0 ONLINE 0 0 0
c7t4d0 ONLINE 0 0
2006 Jun 07
2
help with combination problem
hello:
I have 3 data.frame objects.
First df object:
Of dim (149,31). Columns 2:31 are marked as T1..T14
and N1..N16.
Name T1 T2 N1 T3 N2 N3 N4 T4
mu1 10 10 9 10 9 9 8 10
mu2 11 11 9 11 9 9 9 11
...
muN 12 12 9 11 9 9 8 12
Second df object:
of Dim (50000,31). Columns 2:31 are maked as T1...T14
and N1..N16.
2011 Jan 10
2
Calculating Portfolio Standard deviation
Dear R helpers
I have following data
stocks <- c("ABC", "DEF", "GHI", "JKL")
prices_df <- data.frame(ABC = c(17,24,15,22,16,22,17,22,15,19),
DEF = c(22,28,20,20,28,26,29,18,24,21),
GHI = c(32,27,32,36,37,37,34,23,25,32),
2013 Jan 30
2
Integration of mixed normal distribution
Hi,
I already found a conversation on the integration of a normal
distribution and two
suggested solutions
(https://stat.ethz.ch/pipermail/r-help/2007-January/124008.html):
1) integrate(dnorm, 0,1, mean = 0, sd = 1.2)
and
2) pnorm(1, mean = 0, sd = 1.2) - pnorm(0, mean = 0, sd = 1.2)
where the pnorm-approach is supposed to be faster and with higher precision.
I want to integrate a mixed
2010 Mar 20
2
EM algorithm in R
Please help me in writing the R code for this problem. I've been solving this
for 4 days. It was hard for me to solve it. It's a simulation problem in R.
The problem is
My true model is a normal mixture which is given as
0.5 N(-0.8,1) + 0.5 N(0.8,1). This model has two components.
I will get a random sample of size 100 from this model. I will do this 300
times.
That means, I will have
2008 Apr 05
2
How to improve the "OPTIM" results
Dear R users,
I used to "OPTIM" to minimize the obj. function below. Even though I used
the true parameter values as initial values, the results are not very good.
How could I improve my results? Any suggestion will be greatly appreciated.
Regards,
Kathryn Lord
#------------------------------------------------------------------------------------------
x = c(0.35938587,
2008 Apr 05
2
How to improve the "OPTIM" results
Dear R users,
I used to "OPTIM" to minimize the obj. function below. Even though I used
the true parameter values as initial values, the results are not very good.
How could I improve my results? Any suggestion will be greatly appreciated.
Regards,
Kathryn Lord
#------------------------------------------------------------------------------------------
x = c(0.35938587,
2003 Nov 20
2
reading data rows
I have problems reading a file with more than one row
to carry out mathematical calculations
I have a a file of the form
mu1 mu2 alpha beta Wsigma sigmaA b r
25 15 .05 .05 22 3 .3 .5
30 20 .1 .2 22 .3 .3 .5
I intend to read one row , carry out the calculations
and then the next row with which I intend to do the
same calculations.
I do the following.
2009 May 22
0
EM algorithm mixture of multivariate
Hi, i would to know, if someone have ever write the code to estimate the
parameter (mixing proportion, mean, a var/cov matrix) of a mixture of two
multivariate normal distribution. I wrote it and it works (it could find
mean and mixing proportion, if I fix the var/cov matrix), while if I fix
anything, it doesn't work. My suspect is that when the algorithm iterates
the var/cov matrix, something
2009 May 22
0
EM algorithm mixture of multivariate gaussian
Hi, i would to know, if someone have ever write the code to estimate the
parameter (mixing proportion, mean, a var/cov matrix) of a mixture of two
multivariate normal distribution. I wrote it and it works (it could find
mean and mixing proportion, if I fix the var/cov matrix), while if I fix
anything, it doesn't work. My suspect is that when the algorithm iterates
the var/cov matrix, something