Displaying 20 results from an estimated 500 matches similar to: "Multivariate binary response analysis"
2010 Apr 29
1
How to estimate the residual SD for each sample separately in mixed-effects model?
Dear R-helpers,
I am developing a Mixed-Effects model for a study of immunoassays using
'lme4' library. The study design is as follows: 10 samples were run
using 7 different immunoassays, 3 times each, in duplicates. Data
attached. I have developed the following model:
c.lme <- lmer(Result~SPL + (SPL|Assay/Run) -1, data=data)
This model has excellent predictions - the Rsquared of
2016 Apr 04
2
Evaluating an expression
Hi,
I want to create a data frame similar to the following, but greatly scaled up:
df <- data.frame(aaa= c("a","b","c"), integer(3), integer(3))
names(df)[2:3] <- paste("var",1:2,sep="")
which yields
aaa var1 var2
1 a 0 0
2 b 0 0
3 c 0 0
I would not relish having to paste 'integer(3)' 5000 times :(
2012 Apr 10
3
How to get the SS and MS from oneway.test?
Hello everyone:
I'm a new member of this group.
I have a question about "oneway.test".
When I use "anova(lm(....))" to analysis the
ANOVA,
I can get the information about Sum Sq and Mean
Sq.
(The R code and the results are as follows.)
2008 Dec 07
2
concordance correlation coefficient using R
Hi.
I have data which i would want to assess the degree of agreement
between two assays, e.g., to evaluate reproducibility or for
inter-rater reliability. I have used the Pearson product-moment
correlation coefficient. It looks good ranginging between 0.90 to
0.998. Though this looks good. I am told the Concordance correlation
coefficient will give a better picture of how reproducible the assay
2012 Jun 14
1
Can someone recommend a package for SNP cluster analysis of Fluidigm microarrays?
I know that there are quite a few packages out that there for cluster
analysis. The problem that I am facing is finding a package that will not
incorporate all my samples into clusters but just the samples that fit a
threshold (that I have not set yet and may need help finding the right
level) for genotyping. It should be able to "no call" samples outside the
clusters. It also needs to
2006 Jun 21
1
eliminating a do loop
Using a "by() statement, I am preparing ANOVA's for multiple experiments,
and using simint() to generate confidence intervals.
This works fine.
simint.by.fit <- by(analytes.dfr, list(Assay = analytes.dfr$analyte ),
function(data) (simint(value ~ tx, data = data,type='Tukey' ) ) )
I can separately prepare plots of the confidence intervals, and I can
prepare separate plots
2020 Sep 24
1
How to use `[` without evaluating the arguments.
Hello R-devel,
I am currently attempting to implement an API similar to data.table wherein single bracket subsetting can accept an unquoted expression to be evaluated in the context of my object.
A simple example from the data.table package looks like this:
DT <- data.table(col1 = c('a', 'b', 'c'), col2 = c('x', 'y', 'z'))
DT[col1 ==
2012 Jan 22
1
How to construct a formula
Hi,
I need to construct a formula programaticly, and pass it to a function
such as the linear mixed model lme. The help says it requires "a
two-sided linear formula object describing the fixed-effects part of the
model" but I do not know how to create this formula. I have tried
various things using formula(x, ...), as.formula(object, env =
parent.frame()) and as.Formula(x, ...)
2003 Nov 10
8
Memory issues..
Hi dear R-listers, I'm trying to fit a 3-level model using lme in R. My
sample size is about 2965 and 3 factors:
year (5 levels), ssize (4 levels), condition (2 levels).
When I issue the following command:
>
lme(var~year*ssize*condition,random=~ssize+condition|subject,data=smp,method
="ML")
I got the following error:
Error in logLik.lmeStructInt(lmeSt, lmePars) :
2003 May 12
1
update.lme trouble (PR#2985)
Try this
data(Assay)
as1 <- lme(logDens~sample*dilut, data=Assay,
random=pdBlocked(list(
pdIdent(~1),
pdIdent(~sample-1),
pdIdent(~dilut-1))))
update(as1,random=pdCompSymm(~sample-1))
update(as1,random=pdCompSymm(~sample-1))
update(as1,random=pdCompSymm(~sample-1))
update(as1,random=pdCompSymm(~sample-1))
I'm
2010 Oct 13
5
Regular expression to find value between brackets
Hi,
this should be an easy one, but I can't figure it out.
I have a vector of tests, with their units between brackets (if they have
units).
eg tests <- c("pH", "Assay (%)", "Impurity A(%)", "content (mg/ml)")
Now I would like to hava a function where I use a test as input, and which
returns the units
like:
f <- function (x) sub("\\)",
2017 Aug 08
1
Bug?
Hello,
In my code I found something that looks like an anomaly, I found a reproducible example in which I am just trying to compare each row in a data frame against the first row:
a<-data.frame(row=c("B","C","B"),column=c(2,2,10),assay=c("Assay1","Assay1","Assay1"),plate=c(1,1,1),stringsAsFactors=FALSE)
apply(a[1:2,],1,function(x) {
2004 Mar 15
2
imputation of sub-threshold values
Is there a good way in R to impute values which exist,
but are less than the detection level for an assay?
Thanks,
Jonathan Williams
OPTIMA
Radcliffe Infirmary
Woodstock Road
OXFORD OX2 6HE
Tel +1865 (2)24356
2004 Jan 14
2
Generalized least squares using "gnls" function
Hi:
I have data from an assay in the form of two vectors, one is response
and the other is a predictor. When I attempt to fit a 5 parameter
logistic model with "nls", I get converged parameter estimates. I also
get the same answers with "gnls" without specifying the "weights"
argument.
However, when I attempt to use the "gnls" function and try to
2008 Aug 08
2
[lme4]Coef output with binomial lmer
Dear R users
I have built the following model
m1<-lmer(y~harn+foodn+(1|ass%in%pop%in%fam),family = "quasibinomial")
where y<-cbind(alive,dead)
where harn and foodn are categorical factors and the random effect is a
nested term to represent experimental structure
e.g. Day/Block/Replicate
ass= 5 level factor, pop= 2 populations per treatment factor in each
assay, 7 reps
2005 May 31
1
read.delim2 regarding "#"
Hello R experts:
When I tried to read my data into R, it does not take
# sign
A subset of Exp.txt is:
Experiment name assay id Varname
(A1)DBA TPA 6h/DBA Acetone rep1(A1) #3 4090 A90C1
(A2)DBA TPA 6h/DBA Acetone rep2(A2) #3 4091 A91C1
The command is:
Exp <- read.delim2("Exp.txt",check.names=F,as.is=T)
It is excuted but gave me all the NAs. Can you all
drop me a hint?
Thanks
2005 Jun 22
1
analyzing suvival data using splines (a.k.a., piecewise log-hazard-ratio models)
I'm looking for software that makes plots such as fig 4 (a)-(e), fig 5 anf fig 7
of
Gray, Robert, "Flexible Methods for Analyzing Survival Data Using Splines, with
Applications to Breast Cancer Prognosis," 1992, J Am Stat Assoc, pp 942-51.
In other words, I'm looking for software that takes survival data and a
continuous
covariate as input and computes a curve giving log hazard
2006 Dec 31
4
Does SQL group by have a heavy duty equivalent in R
I have hundreds of humans who have undergone SNP genotyping at hundreds of
loci. Some have even undergone the procedure twice or thrice (kind of an
internal control).
So obviously I need to find those replications, and confirm that the results
are the same. If there is discordance then I need to address it.
I tried to use the aggregate function
nr.attempts
2008 Oct 06
1
Need to calculate within- and between- run CV
Dear R-helpers,
I have a dataset named "qu", organized as follows:
Sample Run Replicate Value
1 1 1 25
1 1 2 40
1 1 3 33
1 1 4 29
1 2 1 37
1 2 2 44
1 2 3 45
1 3 1 25
1 3 2 40
1 4 1 33
1 4 2 29
1 4 3 25
2 ...
Basically, a sample was run on an assay multiple times within a single
day. Each of these results is "Replicate". Then run was repeated several
times in
2011 Nov 21
0
Programmer position in the Gottardo lab at the Fred Hutchinson Cancer Research Center
The Gottardo lab at the Fred Hutchinson Cancer Research Center in Seattle has an opening for a programmer.
To apply:
https://erecruit.fhcrc.org/psp/RECRUIT/EMPLOYEE/HRMS/c/HRS_HRAM.HRS_CE.GBL?Page=HRS_CE_JOB_DTL&Action=A&JobOpeningId=24122&SiteId=2&PostingSeq=1
The position description is below:
About Us
Fred Hutchinson Cancer Research Center, home of three Nobel laureates,