thanks for your reply, Wolfgang! Regarding the dots/circle -"problem" I am relieved now :-)
Regarding the Trim and Fill outcome I don't really think that it's the wrong side, I just dont know how to interpret the result. regtest () reveals a negative z, which is not significant. ranktest () reveals a negative tau, which is not significant. Any ideas? :-) best, Verena On Mon, May 26, 2014 at 2:00 PM, Viechtbauer Wolfgang (STAT) < wolfgang.viechtba...@maastrichtuniversity.nl> wrote: > From help(forest.rma): > > pch -- plotting symbol to use for the observed effect sizes or outcomes. > By default, a solid circle is used. Can also be a vector of values. See > points for other options. > > pch.fill -- plotting symbol to use for the effect sizes or outcomes filled > in by the trim and fill method. By default, a circle is used. Only relevant > when plotting an object created by the trimfill function. > > The defaults are pch=19 and pch.fill=21. So, by default, a solid circle is > used for the observed outcomes and an open circle is used for the outcomes > that are filled in. > > An example is shown here: > > > http://www.metafor-project.org/doku.php/plots:funnel_plot_with_trim_and_fill > > From help(trimfill.rma.uni): > > side -- either "left" or "right", indicating on which side of the funnel > plot the missing studies should be imputed. If left undefined, the side is > chosen within the function depending on the results of Egger's regression > test (see regtest for details on this test). > > The argument is left undefined by default, so the side is chosen based on > the results of the regression test (essentially, whether the slope is > positive or negative). If you think the suppression occurred on the other > side than the one that is chosen, specify the side via this argument. > > Best, > Wolfgang > ________________________________________ > From: r-help-boun...@r-project.org [r-help-boun...@r-project.org] On > Behalf Of Verena Weinbir [vwein...@gmail.com] > Sent: Monday, May 26, 2014 1:15 PM > To: Michael Dewey > Cc: r-help > Subject: Re: [R] Metafor: Strange Trim and Fill Outcome? > > thanks for your reply, Michael! > > ad primary studies: > yup, I have a large set of studies: At the moment I consider 126 data sets > in my analysis. > > ad interpretation: > thats an interesting information. But usually there should be found an > effect. > > ad "bit" :-): > I am irritiated, because in the plots I have studied so far, I always found > that the observed studies are open circles and the additional "mirrored" > effects are black dots. In my case, it is the other way round. > > Also, most of the mirrored circels appear in the right upper corner, > indicating, that there are studies missing in my data set, which have > smaller SDs (i.e. are more precise?) and higher effect sizes? > > best, > > Verena > > On Mon, May 26, 2014 at 12:26 PM, Michael Dewey <i...@aghmed.fsnet.co.uk > >wrote: > > > At 09:34 26/05/2014, Verena Weinbir wrote: > > > >> Hey guys, > >> > >> I have tested the metafor trim and fill function (y:SD, x:SMD)on my data > >> set and yielded the following result: > >> > >> 1. missing studies on the right: 34 > >> > > That seems a lot of missing studies unless you have a very large set of > > primary studies. > > > > 2. open circles on the rights side appear to be the number of additional > >> effects > >> > >> 3. adjusted d would be higher than observed d. > >> > > Implying that the mechanism is suppressing studies which found a large > > effect. This might happen if the dominant view is that there is no effect > > and so when people find one they worry about their results. > > > > Since normally, as I understand, those parameters are the other way > round > >> (black dots indicating missing studies on the left, which would reduce > the > >> effect size), I wonder: > >> > >> Is there a mistake I have done? Or, if this is an actual outcome how > can I > >> interpret this? That its not a publication bias that influences my data > >> set, but a lack of precision (studies missing that are precise -small > SD- > >> and have big SMD)? > >> > > Sorry but that bit is not very clear to me. > > > > Many thanks in advance! > >> > >> Verena > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
