Oops.
I misread the question. There are clearly better ways to do this, than
to use -reshape-.
Nick Winter
-----------------------------------------------------------
Nicholas Winter, Ph.D. P 202.939.5343
Policy Studies Associates F 202.939.5732
1718 Connecticut Avenue, NW [email protected]
Washington, DC 20009-1148 www.policystudies.com
-----------------------------------------------------------
> -----Original Message-----
> From: Nick Cox [mailto:[email protected]]
> Sent: Thursday, October 10, 2002 2:55 PM
> To: [email protected]
> Subject: st: RE: RE: data manipulation
>
>
> Nick Winter
>
> > > I have a dataset which has customer's payment amount by month
> > > by year. Month
> > > ranges from 01 to 12 for years 2000 & 2001 and from 01 to 09
> > > for the 2002. But
> > > all customers don't have data for each month. The dataset
> > > looks like the
> > > following.
> > >
> > > customer month year amount
> > > x1 01 2001 50.45
> > > x1 03 2001 60.00
> > > x2 04 2001 70.00
> > > x2 06 2001 80.00
> > >
> > > I would like to create a data set where each customer will have 12
> > > observations for years 2000 & 2001 and 9 obs. for 2002, and
> > > amount will be
> > > zero for the months they don't have any original data. I
> > > tried with couple of
> > > different ways, but didn't work. Could anyone please help me?
> >
> > Check out the -reshape- command. The only catch is that
> > -reshape- only
> > seems to allow one variable to specify the j() units (the
> > month and year
> > in your case), so you will need to combine them into one
> > variable. One
> > option:
> >
> > gen str7 date = string(year) + "_" + string(month)
> > drop month year
> > reshape wide amount, i(customer) j(date)
>
> This needs to be follow by a -reshape long-.
>
> In principle, the solution will not fill in any gaps
> for the whole data set, i.e. months in which no
> customer made purchases.
> In practice, the enterprise is, we hope, not
> in such a dire state that there are any such gaps.
>
> Nick
> [email protected]
>
> *
> * 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/
