[R] ggplot2, 'se' variable in geom_errorbar's limits?

[Eric Fail]

Can't anybody give me a hint on how to solve this? I even bought the
ggplot2-book, so you could also give a page (or a series of pages).

Thanks,
Eric

On Thu, Feb 17, 2011 at 10:19 AM, Eric Fail <eric.fail at gmx.com> wrote:
>
> Dear R-list
>
> I'm working with with geom_errorbar; specifically I'm trying to
> reproduce the example Hadley Wickham have on
> http://had.co.nz/ggplot2/geom_errorbar.html (all in the button of the
> page) where he makes an nice plot with errorbars and then draw lines
> between the points.
>
> What confuses me is the 'limits' he defines for the errorbars from the
> se variable.
>
> First he creates a dataset,
>
> df <- data.frame(
>  trt = factor(c(1, 1, 2, 2)),
>  resp = c(1, 5, 3, 4),
>  group = factor(c(1, 2, 1, 2)),
>  se = c(0.1, 0.3, 0.3, 0.2)
> )
>
> # library(ggplot2)
>
> and then he creates some limits from the se variables.
>
> limits <- aes(ymax = resp + se, ymin=resp - se)
>
> [elements omitted]
>
> # and then he creates the plot (I'm interested in).
>
> p <- ggplot(df, aes(colour=group, y=resp, x=trt))
> p + geom_line(aes(group=group)) + geom_errorbar(limits, width=0.2)
>
> I can (of course) get Hadley's example to run, but I can't do it on my
> data as I don't have a 'se' variable/don't know how to create it. I
> have a group variable, a treatment variable, and a response variable,
> but no se variable.
>
> Could anyone out there explain how I create a 'se' variable in my data?
>
> I'm sure my reasoning is the one that is off, and not ggplot2 (I'm a big fan).
>
> Your help is appreciated!
>
> Thanks,
> Eric