similar to: metafor

Displaying 20 results from an estimated 500 matches similar to: "metafor"

2007 Mar 12
4
meta-regression, MiMa function, and R-squared
Dear Wolfgang Viechtbauer and list members: I have discovered your "MiMa" function for fitting meta-analytic mixed-effects models through an earlier discussion on this list. I think it is extremely useful and fills an important gap. In particular, since it is programmed so transparently, it is easy to adapt it for one's own needs. (For example, I have found it easy to identify
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
2007 Feb 10
2
error using user-defined link function with mixed models (LMER)
Greetings, everyone. I've been trying to analyze bird nest survival data using generalized linear mixed models (because we documented several consecutive nesting attempts by the same individuals; i.e. repeated measures data) and have been unable to persuade the various GLMM models to work with my user-defined link function. Actually, glmmPQL seems to work, but as I want to evaluate a suite of
2008 Jun 17
1
CIFS VFS errors on strtoUCS in messages log
I have little idea what actions this relates to, but I see about 200 or more of these errors each day in the messages log file: May 29 15:55:41 mima kernel: CIFS VFS: strtoUCS: char2uni of -127 returned -22 No one has complained of a problem. Does anyone know what it signifies? --Donald
2004 Feb 26
1
Distance and Aggregate Data - Again...
I appreciate the help I've been given so far. The issue I face is that the data I'm working with has 53000 rows, so in calculating distance, finding all recids that fall within 2km and summing the population, etc. - a) takes too long and b) have no sense of progress. Below is a loop that reads each recid one at a time, calculates the distance and identifies the recids that fall within 2
2007 Jun 21
3
meta-analysis in R
I would like to combine time-series data to test for correlations and interactions using random and fixed effects meta-analysis. So, I am looking for the right packages and documentation. I know about meta and rmeta packages of R. Are there any more? What are the diffrences in brief? Can you please suggest some references that could be used as a guide for meta-analysis in R (or S-plus)?
2006 Nov 09
2
Meta-regression with lmer() ? If so, how ?
Dear List, I am (again) looking at meta-regression as a way to refine meta-analytic results. What I want to do is to assess the impact of some fixed factors on the results of a meta-analysis. Some of them may be crossed with the main factor of the meta-analysis (e. g. clinical presentation of a disease, defining subgroups in each of the studies under analysis), some of them may be a grouping
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
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 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
2012 Aug 02
1
Metafor package: Including multiple (categorical) predictors
Dear Metafor users, I''d like to test a model with 2 continuous and 2 categorical moderators in a meta regression. One categorical parameter has 2 levels and the other has 4 levels. If I understand correctly, when I include all moderators in the model, Metafor returns main effects of the continuous parameters and contrasts of each level of categorical moderators with the intercept (which
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 Mar 27
1
LME as part of meta-analysis
Hi, I'm having a problem using LME and hopefully I can get some help. Here is what I'm doing: I have a model like this: yi = alpha + theta * xi + beta * zi + error, errors are normally distributed mean 0, var sigma^2 xi and zi are generated from normal distributions within a specified range. True values of alpha, theta, beta and sigma^2 are chosen with a specific mean and variane
2010 Nov 11
1
metafor: including phylogenetic non-independence among species?
Hello, Is it possible to include information about phylogenetic relatedness among species (when species are replicates for each study within a meta-analysis) in a meta-anlaysis in the metafor package? Alternatively, I wonder if the method f Lajeunesse 2009 American Naturalist has been adopted in R in any fashion? Thanks, Scott Chamberlain [[alternative HTML version deleted]]
2012 Jan 14
1
metafor: weights computation in Mantel-Haenszel method
Dear R users, In metafor 1.6-0, the Mantel-Haenszel method is implemented by the rma.mh() function. I have observed that the sum of the weights computed by weights(x) doesn't add to 100% when x is an object of class rma.mh. The consequences of this fact can be clearly seen when a forest diagram is drawn with forest(x), which calls weights(x) (or more precisely, the method weights.rma.mh()
2010 Jun 09
1
back transforming arcsine transformations in metafor
Hi everyone, I'm using the metafor package to meta-analyze a set of proportions. This is working really well for the raw proportions, but is there a way to back-transform the arcsine transformed proportions in the rma or forest functions with the atransf option? The estimates and CIs for the transformed proportions need to be back-transformed to be the sin of the estimate squared.
2011 Jul 18
1
Extract confidence intervals from rma object (metafor package)
Dear R-experts! I am working on some meta-analysis using the metafor package. I would like to extract values of the confidence intervals of the effect sizes of the single studies from an rma object. Those values are printed out when plotting a forest plot using the forest function on the rma object, however I was not able to locate them. Many thanks for your help! Jokel [[alternative HTML
2012 Jul 17
1
tweaking forest plot (metafor package)
Dear All, I'm having trouble tweaking a forest plot made using the R meta-analysis package metafor. I did the analysis based upon the correlation coeff from studies and plotted the corresponding forest plot easily > q2<-rma(yi,vi,mods=cbind(grupo),data=qim) > q2 > forest (q2,transf=transf.ztor,digits=3, ... ,alim=c(0,1),refline=.5) > text(-1.55,42,"Esp?cie