Chau Tak Wai
>
> Originally I have a dataset something like this:
>
> id x1 x2 ...
> 1 10 20
> 2 15 14
> 3 17 17
> .. .. ..
>
> where id is the identifier of that observation and x1, x2,... are
> variables we are going to use for analysis. However, this
> original set
> of data contain some errors needed to be corrected. Now I
> have another
> dataset that contains the error-corrections like this:
>
> id err_var correct
> 1 x1 14
> 1 x2 18
> 2 x1 6
> .. .. ..
>
> where err_var contains the variable name that have
> problems, and correct
> is the corrected value of that variable. I would like to
> seek advice on
> how I can merge the later data set with the first one and
> replace the
> wrong values of the first dataset.
>
This is interesting. My first thought was to -reshape-
the error-corrections data to -wide- and then -merge, update-.
but it would seem likely that the -reshape- would
produce missing values which would then clobber existing
valid values.
So my second thought is to -reshape- the existing data
to -long- and then -merge, update- and then -reshape-
back to -wide-.
Another thought is to read in a text version of
the error corrections data and convert it line
by line into a .do file
e.g.
1 x1 14
becomes
replace x1 = 14 if id == 1
That should be a one-line program in your favourite
scripting language.
Nick
[email protected]
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