R help - Mar 2008 - how to generate bar charts with the standard deviation

Hi,

I have the two vectors mean and sd of individual columns, but I am unsure
how to generate bar charts with the standard deviation, even after looking
the help of barplot and barplot.2.

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Ng Stanley wrote:
> Hi,
> 
> I have the two vectors mean and sd of individual columns, but I am unsure
> how to generate bar charts with the standard deviation, even after looking
> the help of barplot and barplot.2.

Barplots are not well suited for presenting continuous data and many 
would argue that even for proportions, they should not be used to 
present CI's.


You are better off using:

1. plotCI() in the gplots package:

http://cged.genes.nig.ac.jp/RGM2/R_current/library/gplots/man/plotCI.html


2. plotmeans() in the same, which is a wrapper to the above:

http://cged.genes.nig.ac.jp/RGM2/R_current/library/gplots/man/plotmeans.html


3. errbar() in the Hmisc package:

http://cged.genes.nig.ac.jp/RGM2/R_current/library/Hmisc/man/errbar.html


4. arrows() and/or segments() in the default R installation, which can 
be used like errbar() to add CI's to points.


HTH,

Marc Schwartz