Metafor and forest(); not showing 'ilab' and text

Comments in line

On 31/08/2015 16:08, Marco Colagrossi wrote:

Thanks for your help,

I got the mistake I was making and I managed to find a solution
regarding those graphs; I don't want to abuse of your patience but I
have three further questions:

1. Always regarding the forest plots, it is possible to make a
cross-subset? I try to explain my self better; I have one dummy
variable called pub and another variable called SIMiv that can take
the values of "share", "loan", "number" and "duration". How can I
subset my sample so that the forest shows only (for example) studies
when the dummy takes the value of 1 and the SIMiv variable takes the
values of "share" and "loan"?
Something like this:
forest(pc, var, ci95m, ci95p, slab = authoryear2, psize=1,
subset=(pub==1, SIMiv=("share", "loan", "duration"))

Do you not want something like
(pub == 1) & (SIMIv %in% c("share", "loan", "duration"))

2. I have few doubts regarding the multilevel modeling;
     rma.mv(pc, var, random = ~ 1 | author, data=codebook)
    if I'm correct this should be a multilevel model nested at "author"
level; what I cannot understand If it is a varying intercept
(Y=A+BjX), a varying slope (Y=Aj+BX) or a varying intercept&slope
model (Y=Aj+BjX). Are there the formulas for it somewhere? So far I
only found the formulas for the estimators included in the metafor
package.

I think it a random intercept but Wolfgang may correct me there.

3. metareg1 <- rma.mv(pc, var, random = ~ 1 | author, mods = ~ pub +
SIMiv, data=codebook)
Again, if I'm correct this should be a multilevel meta regression
(correct me if I'm wrong); I have the same doubts as before.

Thank you again

Marco

On 25 August 2015 at 19:24, Michael Dewey <lists at dewey.myzen.co.uk> wrote:

Dear Marco

When you change xlim it increases the width of the forest plot in the
sense
you describe. It does not push your text out of the way to make space for
it
but instead overprints it. You may like to use alim to truncate your
confidence interval whiskers to fit within the space you see or make your
labels shorter.


On 25/08/2015 17:25, Marco Colagrossi wrote:

I think I've not explained myself well. When I say "the width of the
forest plot" I mean the region above the observed outcome, the
"actual" forest plot, not the plot as a whole. Even if I change values
for Xlim, cex or ilab.xpos the width of that particular region within
the plot doesn't change.

Best,

Marco

On 25 August 2015 at 18:11, Viechtbauer Wolfgang (STAT)
<wolfgang.viechtbauer at maastrichtuniversity.nl> wrote:

The 'xlim' argument does not change the actual width of the plotting
device. For that, you need to use the 'width' argument with whatever
device
you are actually using. You can then use the 'xlim' argument to create
appropriate spacing to the left/right of the part of the plot that
shows the
estimates and their CIs. Within that space, you can then add additional
columns with the 'ilab' argument. It's up to you to find an appropriate
combination of plotting device width, character/symbol expansion factor
('cex' argument), 'xlim' values, and 'ilab.xpos' values to create a
nice
looking plot that has no overlapping text and no excessive white space.
An
example is this:


http://www.metafor-project.org/doku.php/plots:forest_plot_with_subgroups

Note that it took me dozens of iterations to create that plot. You just
have to start experimenting.

Best,
Wolfgang

-----Original Message-----
From: Marco Colagrossi [mailto:marco.colagrossi at gmail.com]
Sent: Tuesday, August 25, 2015 17:59
To: Viechtbauer Wolfgang (STAT)
Cc: r-help at r-project.org; Michael Dewey
Subject: Re: [R] Metafor and forest(); not showing 'ilab' and text

Thanks again for your help. I'm sorry to bother you but I don't get
how to widen the forest plot; if I try to change the values of xlim or
the ilab.xpos values the width of the forest plot region does not
change, but only moves on the graphs. What I'm I missing?


forest(pc, var, ci95m, ci95p, slab = authoryear, psize=1,
subset=(pub==1),
         xlim = c(-16, 6),
         ilab = data.frame(SIMdv, SIMiv),
         ilab.xpos = c(-7.5, -5.5), cex = 0.75)
op <- par(cex=.75, font=2)
        text(c(-7.5, -5.5), 54, c("DV", "IV"))
        text(-16,                54, "Author(s) and Year",     pos=4)
        text(6,                  54, "Outcome [95% CI]", pos=2)
par(op)

par("usr")[1:2]

[1] -16   6

--
Michael
http://www.dewey.myzen.co.uk/home.html

--
Michael
http://www.dewey.myzen.co.uk/home.html