Re: st: Deleteing all observations for individuals with anomalousdata

[celdjt@umich.edu]

On the other hand, might be an idea to think carefully about your approach to
handling missing data and consider whether there are preferable alternatives.
Perhaps a brief look at Paul Allison little book "Missing Data" as well 
as some
of the multiple imputation programs available to run under Stata.

Quoting Antoine Terracol <Antoine.Terracol@univ-paris1.fr>:


> le 08/08/2005 17:51, Murray Lowe a ecrit :
> > Hi,
> >
> > I am new to Statalist, hope someone can help me!
> >
> > I am working with a large dataset and have discovered that some of the data
> > are missing values or have erroneous values. The data is panel data with
> > observations per individual over a 5 year period. For example:
> >
> > ID	Year	Cost
> >
> > 1	1	100
> > 1	2	200
> > 1	3	500
> > 1	4	150
> > 1	5	x
> > 2	1	100
> > 2	2	200
> > 2	3	500
> > 2	4	600
> > 2	5	100
> >
> > The problem is this: If an individual has a missing / erroneous value for a
> > particular year, I want to exclude ALL of their observations from the
> > dataset. In the example patient 1 would be removed from the dataset
> > entirely. How can this be done through an automated-type process?
> > Essentially I need a code / method that looks for the anomalous data;
> > identifies the patient and then removes all of their observations from the
> > dataset.
> >
> > Hope you can help,
> >
> > Murray Lowe
>
> Hello,
>
> I would try something like :
>
> generate tag=(cost==.)
> egen toberemoved=sum(tag), by(ID)
> drop if toberemoved>0
> drop tag toberemoved
>
>
> You will need to replace the "cost==." in the fisrt line by a more 
> general way to tag your erroneous values (such as "cost==. | 
> cost>9999")
>
> Best,
> Antoine
>
> --
> Ce message a �t� v�rifi� par MailScanner
> pour des virus ou des polluriels et rien de
> suspect n'a �t� trouv�.
>
> *
> *   For searches and help try:
> *   http://www.stata.com/support/faqs/res/findit.html
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/


*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/