Be careful! You are talking about 2 different varieties of apples here. As I read it, the CI's in the cancer data, which I know is just for example purposes, are CI's for the **individual means**; the notches in boxplots are nonparametric and for 2 groups with roughly equal sample sizes, "The idea appears to be to give roughly a 95% confidence interval for the **difference** in two medians." (from ?boxplot.stats). So I'm not sure which you want, but they are certainly different (by a factor of around sqrt(2),right?), even if both are for the mean or both are for the median.
Cheers, Bert On Fri, Jul 5, 2013 at 11:28 AM, David Winsemius <dwinsem...@comcast.net> wrote: > > On Jul 5, 2013, at 11:15 AM, Shaun Jackman wrote: > >> Hi Bert, Dennis, >> >> I'll agree that using a barchart was a poor choice. I was in fact using a >> notched bwplot to show the median and confidence interval of the median. In >> this case it's the median and confidence interval that I want to highlight, >> and I find that the visual noise of the box and whiskers is detracting from >> the focus, and those wee notches are not much to focus on. So, I'd like to >> draw a stripplot with error bars, preferably in Lattice. Let's call this a >> TIE fighter plot. Any suggestions? >> > > I like the TIE fighter label. Try this: > > library(latticeExtra) > data(USCancerRates) > segplot(reorder(factor(county), rate.male) ~ LCL95.male + UCL95.male, > data = subset(USCancerRates, state == "Washington"), > draw.bands = FALSE, centers = rate.male, > segments.fun = panel.arrows, ends = "both", > angle = 90, length = 1, unit = "mm") > > It's what Sarkar has recommended in the past when this request has been > posted. > > -- > David > > >> Cheers, >> Shaun >> >> On 4 July 2013 18:00, Dennis Murphy <djmu...@gmail.com> wrote: >> >>> If you consult the lattice package help, you'll discover there is no >>> panel_errorbar() function, which would imply the package developers >>> have a distaste for that type of graphic. If you fish around the >>> R-help archives, though, you might be able to find someone who wrote a >>> function to do error bars in lattice. (Use a searchable archive such >>> as Nabble to hunt for it.) >>> >>> Error bar plots are easier to do in the ggplot2 package, since there >>> is a specific function to generate the error bar 'geometry' >>> (geom_errorbar). See http://docs.ggplot2.org/current/ for an expanded >>> version of the package help pages, which include the graphs generated >>> by the code. I believe there's also a base graphics version that you >>> can get from the gplots package, but I don't know a lot about it. >>> >>> Dennis >>> >>> On Thu, Jul 4, 2013 at 2:53 PM, Shaun Jackman <sjack...@gmail.com> wrote: >>>> Hi, >>>> >>>> I'd like to draw a lattice barchart of means with error bars to show >>>> the standard deviation. I have the barchart, how do I add the error >>>> bars? >>>> >>>> require(datasets) >>>> require(lattice) >>>> x <- aggregate(weight ~ Diet, ChickWeight, function(x) c(mean=mean(x), >>>> sd=sd(x))) >>>> barchart(weight[,'mean'] ~ Diet, x) >>>> >>>> Thanks, >>>> Shaun >>>> >>>> ______________________________________________ >>>> 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. >>> >> >> [[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. > > David Winsemius > Alameda, CA, USA > -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.
