Re: st: Generating mean by two groups

["Alan Neustadtl" <alan.neustadtl@gmail.com>]

The following should work:

bysort L D: egen M=mean(P)

Best,
Alan

On 1/9/07, Z. Aloha <mai7777@gmail.com> wrote:
> Hi,
> How can I generate a mean by two groups. That is I have different
> location allocations (L)  and different dates (D), and I would like to
> generate a new variable (M) that contains the mean of the price (P)
> within each location on each date. An example is listed below:
> P       L       D      M
> 1       A       1     1.5
> 2       A       1     1.5
> 3       B       1      3
> 3       B       1      3
> 5       A       2      5.5
> 6       A       2      5.5
> 3       B       2       5
> 7       B       2       5
> 2       A       3       3.5
> 5       A       3       3.5
> 4       B       3       6
> 8       B       3       6
> 12      A       4      8
> 4       A       4       8
> 6       B       4       4
> 2       B       4       4
*
*   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/