R help - May 2013 - Very basic statistics in R

Dear all,

Very simple question, but apparently uneasy to solve in R:

I have a sampling of a variable x: (3, 4. 5, 2, ...)

I want to know:
 - the mean <x>                   -> mean(x)
 - the uncertainty on <x>       -> std.error(x) ? Or sd(x)?
 - the standard deviation of x  -> ?
 - the uncertainty on the standard deviation -> ?

Anyone has an idea?

Thanks in advance,

regards,
Xavier



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Xavier Prudent
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>  - the mean <x>                   -> mean(x)
>  - the uncertainty on <x>       -> std.error(x) ? Or sd(x)?
>  - the standard deviation of x  -> ?
>  - the uncertainty on the standard deviation -> ?
> 
> Anyone has an idea?
1. Use R's help system to look up 'standard deviation' and
'mean'
e.g.:
??'standard deviation' 
??'mean'

For the other two questions, consult your basic stats textbook; the answers can
be calculated from the two above together with the number of observations.

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This email and any attachments are confidential. Any use...{{dropped:8}}

I recommend you read the Introduction to R document that comes with R. Look for
making vectors with the c() function, and using the mean() and sd() functions.

Note that this is not a homework help forum (read the Posting Guide mentioned at
the bottom of every message). If this is not homework, you are going to need to
do quite a bit of self study before you can ask questions clearly enough to get
useful responses on this list. See

http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example
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Xavier Prudent <prudentxavier at gmail.com> wrote:
>Dear all,
>
>Very simple question, but apparently uneasy to solve in R:
>
>I have a sampling of a variable x: (3, 4. 5, 2, ...)
>
>I want to know:
> - the mean <x>                   -> mean(x)
> - the uncertainty on <x>       -> std.error(x) ? Or sd(x)?
> - the standard deviation of x  -> ?
> - the uncertainty on the standard deviation -> ?
>
>Anyone has an idea?
>
>Thanks in advance,
>
>regards,
>Xavier