# [R] Help needed

Gavin Simpson gavin.simpson at ucl.ac.uk
Fri Jan 28 11:52:36 CET 2011

```On Thu, 2011-01-27 at 09:50 -0500, Thomas Stewart wrote:
> For question 2,
>
> TTT <- rt(1000,3)
> mean(TTT[rank(TTT) <= 975 & rank(TTT) >25])

mean(TTT, trim = 0.05)

What you are doing is only removing 5% of observations in total, whilst
the question asks for 5% removed off *each* end.

G

>
> On Thu, Jan 27, 2011 at 8:16 AM, Ben Boyadjian <benjy_cy_21 at hotmail.com>wrote:
>
> > Hello I am trying to solve these problems and I am not allowed to use loops
> > or ifs.
> >
> > 1st Question
> > My first question is that I have generated 100 random numbers from the
> > uniform distribution then
> > A)add only the negative integers.
> > B)add elements until the first appearance of a negative element.
> >
> > I know how to choose the negative elements for A but how to find integers?
> > And I dont know what to do for B.
> >
> > 2nd Question
> >  Simulate 1000 observations from the student-t distribution with 3 degrees
> > of freedom and then calculate the truncated mean by excluding bottom 5% and
> > top 5%.
> >
> > Thank yoou
> >
> >
> >        [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-help at 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 at 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.

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Dr. Gavin Simpson             [t] +44 (0)20 7679 0522
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