If the data is ordered by id, the variable id itself is the trend and
you can use as your independent variable to interpolate:
ipolate var1 id, gen(var1i)
_______________________
Jorge Eduardo Pérez Pérez
On Sun, Jan 31, 2010 at 6:25 PM, Song <[email protected]> wrote:
>
> Dear all,
>
> I would like to fill the missing value in var1 based on the trend of the
> same variable (=var1) instead of using additional independent variable.
> However, "ipolate" requires an independent variable. How can I fill the
> missing value based on the trend of the variable itself? I would like to use
> exponential decay for var1, but a linear trend is also fine.
>
> id var1
> 1 45
> 2 37
> 3 32
> 4 31
> 5 17
> 6
> 7 3
> 8 1
>
> Thank you in advance.
> Mike.
>
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