Please ignore this question - I sent it before receiving Michael Blasnik's
nice solution. For some reason it didn't reach the list until now. Thanks
again to Michael.
Daniel
> A revision to my question: I can now see that creating X_AVG is not
> difficult, except for the case of multiple observations with the same
> date.
> However, I still need help to create X_AVG without using values of X that
> share the same date. Thanks. Daniel
>
> At 02:40 PM 10/18/2006 -0400, you wrote:
>>Hi - I have data on a variable, X, for a set of individuals. Each
>>observation also has the date that X was recorded. I want to create a new
>>variable, X_AVG, which is the mean value of X for all observations with a
>>date that precedes the date for the current observation. X_AVG would be a
>>moving average, that would incorporate all observations with earlier
>> dates.
>>
>>Example:
>>
>>Obs Date X X_AVG
>>1 1/1/2004 4 .
>>2 1/2/2004 3 4
>>3 1/4/2004 5 3.5
>>4 1/5/2004 2 4
>>5 1/8/2004 8 3.5
>>6 1/10/2004 5 4.4
>>7 1/10/2004 8 4.4
>>8 1/11/2004 3 5
>>
>>I want to know how to create X_AVG. And, in particular, is there a way to
>>deal with cases like observation 7, which has the same date as
>> observation
>>6. In that case, I would not want to use the value of X in observation 6
>>to create X_AVG for observation 7.
>>
>>I hope that this is clear enough. Thanks. Daniel
>>
>>*
>>* 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/
>
*
* 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/
