[R] summary statistics

[stephen sefick]

Jim,
prettyR looks like it will work, but with the way that my data frame
is set up I still can not get what I want out of it.  I am lacking in
my knowledge on manipulating data frames, and general R programing.
Is there a reference that will give me all of these wonderful data
manipulation tools that previous posters in this thread have sighted:

>tapply(x$mgl, x$RM, summary)

I read the help file for tapply and I still don't entirely understand
it.  I am a biologist trying to learn R because it serves my purposes-
I am not a programmer; however, I see the utility enough to be right
stubborn when it come to learning this.  I am fully aware that I am
not competent in programing, but I do know the the theory behind the
analyzes that I am performing, which, granted, are not all that
sophisticated (mostly descriptive statistics, community data
ordination, and time series analysis).  My main complaint is I don't
know which way to put a data frame into R to let it proceed with the
analysis.  I preprocess most of my data in excel- this is a convention
imposed by the kind of data and knowledge of the rest of the folks
that are in my lab.  Is there a succinct reference for programing in
R(S+) on how to rearrange data once inside of R, and maybe a general
guide for matrix/ data frame setup for general analysis and what "way"
something should look for different kinds of analysis.  I am learning
and, most of the time, I can generate graphs etc. faster than in
excel, but sometimes I spend hours trying to "get the data in the
right format" and then three minutes of actual coding and result
generation.  Maybe I'm out of my league, but I am not content with
giving my data over to somebody else to do the analysis because
relativley more knowledge on how a river system works.
thanks everybody for the continuing help

Stephen

On Feb 13, 2008 5:03 AM, Jim Lemon <jim at bitwrit.com.au> wrote:
> stephen sefick wrote:
> > below is my data frame.  I would like to compute summary statistics
> > for mgl for each river mile (mean, median, mode).  My apologies in
> > advance-  I would like to get something like the SAS print out of PROC
> > Univariate.  I have performed an ANOVA and a tukey LSD and I would
> > just like the summary statistics.
>
> Hi Stephen,
> Have a look at "describe" in the prettyR package. You can specify the
> summary stats that you want, and the formatting may suit you.
>
> Jim
>
>



-- 
Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods.  We are mammals, and have not exhausted the
annoying little problems of being mammals.

								-K. Mullis