# [R] Division of data set with some restriction

Bert Gunter bgunter.4567 at gmail.com
Mon Jan 25 21:59:11 CET 2016

```Muhammed:

1. Please post in plain text, not HTML, as HTML tends to get mangled
(this is the stated policy on this list). This may have happened to
your post, so I am not entirely sure what you want.

2. However, an assumption that you appear to be making is false: it is
not in general possible to split a data set with a given mean into two
subsets each of which has the same mean, i.e. average. A simple
counterexample is the data set 1, 9,  50  which has a mean of 20 but
cannot be split into 2 subsets with that mean.

3. If this is not what you meant, than you may need to clarify, as it
is certainly unclear to me.

Cheers,
Bert

Bert Gunter

"The trouble with having an open mind is that people keep coming along
and sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )

On Mon, Jan 25, 2016 at 12:12 PM, Muhammad  Kashif <mkashif at uaf.edu.pk> wrote:
>
> Dear Group members
>
> Can any one help to code this situation. Suppose we have a population with some mean  and a standard deviation. Then  , there are n1 observations out of n  which are less than or equal to n . Also, there are n2 observations out of n which are greater than  . We divide the whole data set into two parts such that we have the same mean   but different standard deviations.
>
> for example we have 50 observations from any distribution say two parameter Weibull. Then we divide the data into two parts such that the two resulting data sets have same mean and different standard deviation.
>
>
>
>         [[alternative HTML version deleted]]
>
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