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Dear lme4-Maintainers, As far as I can tell, lmList() from lme4 does not play nicely with grouped data objects from the nlme package. Example: library(lme4) data(Orthodont, package="nlme") class(Orthodont) ### [1] "nfnGroupedData" "nfGroupedData" "groupedData" "data.frame" res...

That's definitely one for the fortune package! Wolfgang > -----Original Message----- > From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] > On Behalf Of Frank Harrell > Sent: Monday, February 14, 2011 14:50 > To...

For ML/REML estimation, you can also use metafor, mvmeta, and metaSEM. An illustration of a multivariate meta-analysis with the metafor package can be found here: http://www.metafor-project.org/doku.php/analyses:berkey1998 Best, Wolfgang -- Wolfgang Viechtbauer...

I've updated: http://www.metafor-project.org/doku.php/analyses:vanhouwelingen2002 It now shows how to get the regression of the underlying effects and also how to draw the confidence ellipse. The 5.99 comes from qchisq(.95, df...

Dear All, I have been checking the metafor package against R-devel. R CMD check --as-cran metafor yields one note: FOSS licence with BuildVignettes: false Yes, I have 'BuildVignettes: FALSE' in my DESCRIPTION file. I see at http://developer...

See FAQ 7.31: http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f And try this: 25000*(1-.55) - 11250 25000*.45 - 11250 Notice a difference? Best, -- Wolfgang Viechtbauer...

Dear All, Just wondering: Is there any official policy on announcing R-related courses and books on r-help? I didn't find anything on this in the posting guide, but http://www.r-project.org/mail.html#instructions says...

No, x and y are not unique. In fact, there is an infinite number of x and y pairs that are roots to the equation P[X<x, Y<y] = 0.05. -- Wolfgang Viechtbauer ?Department of Methodology and Statistics ?University...

Correct. -- Wolfgang Viechtbauer http://www.wvbauer.com/ Department of Methodology and Statistics Tel: +31 (0)43 388-2277 School for Public Health and Primary Care Office Location: Maastricht University, P.O. Box 616 Room B2.01 (second floor) 6200 MD...

But the second column in coef(summary(ols1)) gives you the SE, so why not use that? Otherwise, you may want to look into the 'multcomp' package and its glht() function. Best, Wolfgang > -----Original Message----- > From: R-help [mailto:r...

You can get an OR from a 2x2 table (which is equivalent to doing logistic regression with a single dummy variable that indicates the group) or from some continuous exposure (where the logistic regression model will then include that continuous...

What you are describing is a path model (e.g., http://bit.ly/f4siTs). You can fit such a model with the sem package (http://cran.r-project.org/web/packages/sem/index.html). Best, -- Wolfgang Viechtbauer Department of Psychiatry...

Thanks for the feedback. At least on Windows, the font size for View() appears to be controlled by the font size specified under the Rgui preferences / Rconsole. I thought that under Linux, it might be controlled by some .Xresources/.Xdefaults...

Let r_1 be the correlation between the two variables for the first group with n_1 subjects and let r_2 be the correlation for the second group with n_2 subjects. Then a simple way to test H0...

The constraint b1=b2 in a model such as b0 + b1 x1 + b2 x2 + b3 x3 implies that b0 + b1 (x1 + x2) + b3 x3, so just add x1 and x2 (call this x12) and fit the model b0 + b1 x12...

Hi Gabriele, Yeah, that syntax isn't correct. I think/assume you meant: res <- rma.mv(yi, vi, random = list(~ 1 | Experiment/nadd, ~ 1 | Species), data=dat) Best, Wolfgang >-----Original Message----- >From: R-sig-meta-analysis [mailto:r-sig-meta...

The MSE of an estimator X for a parameter theta is defined as E(X - theta)^2, which is equal to Var[X] + (Bias[X])^2, so in that sense, the MSE is already taking the bias of X into...

1) Ni is the total sample size of a study. For multitreatment studies, this is the control group size plus the sizes of the treatment groups. 2) Unfortunately, no. The code given there is specifically for the standardized mean difference...

You will have to enter the external IP address and then use port forwarding. Just google for that term (port forwarding) ... For example: http://www.howtogeek.com/66214/how-to-forward-ports-on-your-router/ http://en.wikipedia.org/wiki...

To clarify the last point - you have two options: 1) Fit the model with: res <- rma(logrr, sei=sei, ni=ni, method="DL", data=data) assuming that 'ni' is the name of the variable in 'data' that contains the total...