Displaying 20 results from an estimated 1000 matches similar to: "metafor: including phylogenetic non-independence among species?"
2013 Jun 03
1
Mixed effects model with a phylogenetic tree/ distance matrix as a random effect
Hi,
I'm trying to build a mixed-effects model in which I'd like to include
either a distance matrix or a phylogenetic tree as a random effect.
The troubles I've had are that:
1. Function lmer() in package lme4 only accepts a data frame column as a
random factor and not a distance matrix.
2. Function MCMCglmm() in package MCMCglmm only accepts a rooted and
ultrametric phylogenetic
2011 Apr 14
1
Overlaying images at nodes of phylogenetic tree
Can you recommend an R library that will help me create a diagram of a
phylogenetic tree on which specific images are placed at appropriate nodes of
the tree?
For example, I have specific image files associated with each member of the
phylogenetic tree, and I would like to automate the display of the image next to
the correct node of the tree. I can provide an image file with an example.
2007 Jan 26
1
Package for phylogenetic tree analyses
Hi
I am looking for a package that
1. reads in a phylogenetic tree in NEXUS format
2. given two members/nodes on the tree, can return the
distance between the two using the tree.
I came across the following packages on CRAN
ouch, ape, apTreeShape, phylgr all of which seem to
provide extensive range of functions for reading in a
Nexus-format tree and performing phylogenetic
analyses, tree
2011 Jan 12
1
Metafor vs Meta vs Spreadsheet: wrong numbers
Hello,
I experimented the Metafor and Meta packages in the scope of replacing Excel
for meta-analysis. I performed the first working example provided in Michael
Borenstein's book "Introduction to Meta-Analysis" with Excel, Metafor and Meta.
The numbers given by my spreadsheet, which I validated from Borenstein's book,
conrespond quite closely to those given by Meta, but
2009 Aug 13
1
metafor random effects meta-analysis
Hello,
Great to see the new metafor package for meta-analysis.
I would like to perform a meta-analysis in which I initially calculate the intercept of the model with a nested random-effects structure. In lme, this would be
model<- lme(v3~1, random=~1|species/study, weights = varFixed(~Wt), method = "REML")
where multiple effects sizes are measured for some studies and more than
2009 Jul 24
1
metafor
I had found the author's (Wolfgang Viechtbauer) earlier meta-analytic code in R, MiMa, useful. so I have been exploring metafor using an example dataset from MiMa. metafor provides a lot more. However, MiMa provided parameter estimates, standard errors, z values, etc. for individual moderators in the meta-analysis, but I don't see how to obtain these from metafor. Have you any help
2013 Mar 15
1
metafor - multivariate analysis
Dear Metafor users, I'm conducting a metaanalysis of prevalence of a particular behaviour based on someone elses' code. I've been labouring under the impression that this:
summary(rma.1<-rma(yi,vi,mods=cbind(approxmeanage,interviewmethodcode),data=mal,method="DL",knha=F,weighted=F,intercept=T))
is doing the multivariate analysis that i want, but have read that
2009 Sep 17
1
How to colour the tip labels in a phylogenetic tree
Hi,
Using Ape, I have constructed an object of class "phylo", using the
method 'nj' (lets call the object 'tree_ja').
I also have a given subset of 'tree_ja' in a vector (lets call the
vector 'subspecies').
What I want to do, is construct a nj tree - plot(tree_ja) - but have the
species in vector 'subspecies' shown as red at the tips of the
2011 Aug 17
3
questions about "metafor" package
Hello,
I would like to do a meta-analysis with the package « metafor ». Ideally I would like to use a mixed model because I’m interested to see the effect of some moderators. But the data set I managed to collect from literature presents two limits.
- Firstly, for each observation, I have means for a treatment and for a control, but I don’t always have corresponding standard
2011 Oct 03
1
Meta-analysis of test statistics in "metafor" package?
Hi -
I am conducting a meta-analysis and I have a matrix of f-statistics, Ns and
dfs from a series of studies that tested for an interaction in a 2x2 anova.
I'd like to test whether the 2x2 interaction is significant in the
aggregate.
Similarly, I have a matrix of chi-square statistics that I'd like to
meta-analyze.
How can I input these test statistics into the "metafor"
2012 Jan 11
1
meta-analysis normal quantile plot metafor
Hello,
I once used the metawin software to perform a meta-analysis (see
metawinsoft, Rosenberg et al.) and produced normal qqplot to test for
a potential bias in the dataset.
I now want to re-use the same dataset with the package metafor by W.
Viechtbauer (great package btw).
I run the qqnorm.rma.uni function. I use standardized effect sizes as
in metawin.
QQplot generated with metafor differs
2012 Sep 07
2
metafor package: study level variation
Hello. A quick question about incorporating variation due to study in the metafor package. I'm working with a particular data set for meta-analysis where some studies have multiple measurements. Others do not. So, let's say the effect I'm looking at is response to two different kinds of drug treatment - let's call their effect sizes T1 and T2. Some studies have multiple
2012 Aug 01
1
"metafor" package, proportions: single groups wrt to a categorical dependent variable
Dear Dushanthi,
Please keep your e-mails on the R-Help list, where Michael has already given you some excellent advice. As Michael already explained, metafor can handle proportions, but does not have any specific functionality for categorical variables with more than 2 levels (at the moment). So, if it is logical and possible to do so, you could collapse the levels of the categorical outcome to 2
2011 Jan 12
1
metafor/ meta-regression
Hi I have tryed to do the meta-regression in metafor package, but I
would like to get the standardized coefficients for each variable, however in
command:
Ø res<-rma.uni (yi, vi,
method="REML", mods=~cota+DL+uso+gadiente+idade, data= turbidez)
I just have the coefficients no standardized (estimate) of the multiple
regression.
What I need to do?
Thanks
Fernanda Melo
2013 Dec 12
1
refline in forest() {metafor}
Hello all,
I am using forest.rma to plot a random effects model meta-analysis. I noticed
that refline sets a vertical line indicating the null hypothesis.
Is there a way to draw another vertical line, possibly dashed, centered on the
summary estimate?
Prof. Viechtbauer, if you happen to read this, I'd like to thank you for making
an excellent package. I have been using the metafor package
2009 Nov 13
1
multivariate meta-analysis with the metafor package
Dear Wolfgang Viechtbauer and R users,
I have few questions regarding the development of the package 'metafor.
As you suggested , I post to the R-help mailing list.
I read you're planning an extension of this method to the multivariate case.
I think it would be a useful tool.
I'm currently performing some analyses with R on multiple outcomes, using the Stata command mvmeta to get
2005 Jan 03
1
building phylogenetic trees
Hello,
My name is Sivan and I am a master degree student in statistics,my problem is as follows:
I have a dataset containing gene sequences and I would like to create a phylogenetic tree from it.
The problem that I can't seem to find a function to do this kind of operation. I read the ape package manual and I haven't found a command that takes raw data and turns it into a tree.
does anyone
2013 Jan 23
1
mixed effects meta-regression: nlme vs. metafor
Hi,
I would like to do a meta-analysis, i.e., a mixed-effects regression,
but I don't seem to get what I want using both the nlme or metafor packages.
My question: is there indeed no way to do it?
And if so, is there another package I could use?
Here are the details:
In my meta-analysis I'm comparing different studies that report a
measure at time zero and after a certain followup
2009 Jun 05
1
New Meta-Analysis Package (metafor)
A new package is now available via CRAN, called metafor.
The metafor package consists of a collection of functions for conducting meta-analyses in R. Fixed- and random-effects models (with and without moderators) can be fitted via the general linear (mixed-effects) model. For 2x2 table data, the Mantel-Haenszel and Peto's method are also implemented. The package also provides various plot
2012 Apr 04
1
using metafor for meta-analysis of before-after studies
Greetings,
I wish to conduct a meta-analysis for which the outcome is a continuous
variable measured on the same individuals before and after an intervention.
Hence, the comparison is not made between two groups, but within groups, at
diffrent times.
Each study reports the mean outcome and SD before the intervention and the
mean outcome and SD after the intervention. While p-values for