Displaying 20 results from an estimated 10000 matches similar to: "Problem with indexing"
2003 Apr 02
2
lme parameterization question
Hi,
I am trying to parameterize the following mixed model (following Piepho
and Ogutu 2002), to test for a trend over time, using multiple sites:
y[ij]=mu+b[j]+a[i]+w[j]*(beta +t[i])+c[ij]
where:
y[ij]= a response variable at site i and year j
mu = fixed intercept
Beta=fixed slope
w[j]=constant representing the jth year (covariate)
b[j]=random effect of jth year, iid N(0,sigma2[b])
a[i]=random
2005 Jun 15
2
need help on computing double summation
Dear helpers in this forum,
This is a clarified version of my previous
questions in this forum. I really need your generous
help on this issue.
> Suppose I have the following data set:
>
> id x y
> 023 1 2
> 023 2 5
> 023 4 6
> 023 5 7
> 412 2 5
> 412 3 4
> 412 4 6
> 412 7 9
> 220 5 7
> 220 4 8
> 220 9 8
> ......
>
Now I want to compute the
2008 Mar 15
2
Please find the error in my code
hello everybody
I use the following code for my programming & it runs with the error as specified below.Any help that would disolve the error will be highly appreciated.
Thanks in advance
my code looks like this
#### R programme for simulating the power of the two sample t test vs various
#### non-parametric alternatives
sim.size <- 200
sample.size <- 10
set.seed(231)
mu1 <- 0
delta
2007 May 17
1
use loop or use apply?
Hi,
I have two matrices, A (axd) and B (bxd). I want to get another matrix C (axb)
such that, C[i,j] is the Euclidean distance between the ith row of A and jth
row of B. In general, I can say that C[i,j] = some.function (A[i,], B[j,]).
What is the best method for doing so? (assume a < b)
I have been doing some exploration myself: Consider the following function:
get.f, in which,
2004 Nov 16
1
Pairwise Distances -- How to vectorize the loop
R-List,
I'm trying to compute pairwise distances among pairs of observations,
which each pair containing data from 2 groups. There are more than
100000 unique pairs. I have programmed a distance function that has
three parameters, a vector of covariates from the ith observation in
Group 1, a vector of covarites from the jth observation in Group 2, and
a weighting matrix.
I have used
2006 Oct 02
1
multilevel factor model in lmer
Hello --
I am curious if lmer can be used to fit a multilevel factor model such as a
two-parameter item response model. The one parameter model is
straightforward. A two-factor model requires a set of factor loadings
multiplying a single random effect. For example, a logit model for the ith
subject responding correctly to the jth item (j=1,..,J) is
logit[p(ij)] = a1*item1(i) + ... + aJ *
2007 Oct 29
1
How to test combined effects?
Suppose I have a mixed-effects model where yij is the jth sample for
the ith subject:
yij= beta0 + beta1(age) + beta2(age^2) + beta3(age^3) + beta4(IQ) +
beta5(IQ^2) + beta6(age*IQ) + beta7(age^2*IQ) + beta8(age^3 *IQ)
+random intercepti + eij
In R how can I get an F test against the null hypothesis of
beta6=beta7=beta8=0? In SAS I can run something like contrast age*IQ
1,
2002 Dec 06
6
fast code
Hello,
I have two vectors x1 and x2 both in increasing order.
I want to select the x1[j]th entry which is the max min of the x2[i]th
entry. I can do this using if and for statements but is there a quick way
to do it without running a loop?
Thank you in advance,
Pantelis
2009 Dec 28
2
Modified R Code
Dear R helpers,
I have following input files. (Actually they are more than 10 rates but here i am considering only 2 rates to write my problem)
rate1.csv
min1 max1 min2 max2 min3 max3
1.05 1.30 1.30 1.65 1.65 1.99
rate2.csv
min1 max1 min2 max2 min3
2007 Sep 18
0
[LLVMdev] 2.1 Pre-Release Available (testers needed)
On Saturday 15 September 2007, Tanya Lattner wrote:
> 2) Download llvm-2.1, llvm-test-2.1, and the llvm-gcc4.0 source.
> Compile everything. Run "make check" and the full llvm-test suite
> (make TEST=nightly report).
I tried to do this, but ran into trouble.
LLVM itself compiled fine.
GCC compilation is broken when Java support is enabled. I can file a detailed
bug report
2005 Nov 04
1
t test on data frame
Hi,
I have constructed a dataframe as follows:
Oil <- rep(c("Oil1","Oil2","Oil3"),8)
Comp <- rep(rep(c("C1","C2"),c(4,4)),3)
Mth <- rep(c("M1","M1","M2","M2"),6)
Meas <- rep(c(1,2),12)
Result <- rnorm(24,mean=100, sd=5)
df <- data.frame(Oil, Comp, Mth, Meas, Result)
The same compound
2008 Jan 16
2
old master.pid prevents dovecot startup
Summary
=======
After an unclean shutdown the file /var/run/dovecot/master.pid remained
behind. This prevented dovecot from starting, and gave a misleading error
message.
To be more resilient and fault-tolerant, I recommend that dovecot also
check the validity of the PID in /var/run/dovecot/master.pid in order to
determine whether or not another dovecot process is running.
Detail
======
In
2013 Apr 06
1
Replace missing values within a group with the non-missing value
I have a large dataset organised in choice groups see below. Each choice represents a separate occasion with 1 product chosen out of the 6 offered.
+-------------------------------------------------------------------------------------------------+
| dn obs choice acid br date cdate situat~n mth year set |
2007 Nov 15
5
Multiply each column of array by vector component
Hi,
I've got an array, say with i,jth entry = A_ij, and a vector, say with jth
entry= v_j. I would like to multiply each column of the array by the
corresponding vector component, i,e. find the array with i,jth entry
A_ij * v_j
This seems so basic but I can't figure out how to do it without a loop.
Any suggestions?
Michal.
2013 Apr 06
2
Replace missing value within group with non-missing value
Dear List members
I have a large dataset organised in choice groups see sample below
+-------------------------------------------------------------------------------------------------+
| dn obs choice acid br date cdate situat~n mth year set |
2007 Apr 23
1
How to get LSMEANS from linear mixed model?
Hi there,
I am trying to run simulations using R with linear mixed model (lme). There
are two factors in my fixed effect model, educ (treatment and control) and
mth (visit 1, 2, and 3). What I want to obtain is the estimated treatment
difference (treatment - control) at visit 3, plus the standard error and
p-value. This can be easily obtained in SAS using lsmeans or estimate
statements, but I
2008 Mar 25
0
Mixed-effects models: question about the syntax to introduce interactions
hello everyone,
I would like to as for advice for the use of ?lmer?
(package ?lme4?) and writing the proper syntax to best
describe my data using a mixed-effects model.
I have just started to use these models, and although
I have read some good examples (Extending the Linear
Model with R, Faraway 2005; and the R book, Crawley
2007), I am still not sure of the syntax to test my
hypothesis.
2011 Sep 28
1
Multiplying a list of matrices with a vector
Hi all!
I have a list of matrices and I want to multiply the ith element of the list with the ith element of a another vector. That is,
> LL <- list(A=diag(3),B=diag(3),C=diag(3))
> vec <- 1:3
> for(i in 1:3)
+ {
+ LL[[i]] <- LL[[i]]*vec[i]
+ }
> LL
$A
[,1] [,2] [,3]
[1,] 1 0 0
[2,] 0 1 0
[3,] 0 0 1
$B
[,1] [,2] [,3]
[1,] 2 0
2009 Jan 06
5
Using apply for two datasets
I can run one-sample t-test on an array, for example a matrix myData1,
with the following
apply(myData1, 2, t.test)
Is there a similar fashion using apply() or something else to run
2-sample t-test with datasets from two groups, myData1 and myData2,
without looping?
TIA,
Gang
2010 Aug 28
1
star models
Hi,
I am traying to implement an STAR model, but I have some problems.
I am following the instruction of the model, that they are in:
http://bm2.genes.nig.ac.jp/RGM2/R_current/library/tsDyn/man/star.html
that they are from:
http://bm2.genes.nig.ac.jp/RGM2/pkg.php?p=tsDyn
The model is:
star(x, m=2, noRegimes, d = 1, steps = d, series, rob = FALSE, mTh,
thDelay, thVar, sig=0.05, trace=TRUE,