Hello,
My knowledge about Stata is limited and a feel ashamed that i have to bother you with my question because maybe I just made a stupid mistake in the command that I use. But I really do not know how I can solve the problem and I could not find a solution on the internet.
I want to use the following command:
. levpet logSales, free(logEmployees) proxy(logMaterials) capital(logCapital) i(number) t(Year) revenue
I get the following error:
repeated time values within panel
r(451);
I have no idea why i get the ''repeated time values within panel'' error. I am 100% sure that there are no duplicates:
. dupliactes list Year number
result: no observations are duplicates
By only using a part of my dataset i get an idea what the problem is:
. levpet logSales if (NACE<=1531), free(logEmployees) proxy(logMaterials) capital(logCapital) i(number) t(Year) revenue
Now I get the results of the levpet command. However there is something strange:
Dependent variable represents revenue. Number of obs = 148
Group variable (i): number Number of groups = 5756
Time variable (t): Year
Obs per group: min = 1
avg = 4.1
max = 5
The number of observations is 148 and the number of groups is 5756? Then I see that the average number of observations per group is 4.1 This means that the number of groups should be 36 and not 5756.
I really have know idea what is going wrong. I just like to get the levpet results for my whole dataset. The . help levpet command do not give me the answer. Others papers that I have read and that are using the levpet command are telling that it is straightforward to use the levpet command.
Can someone help me
Yours sincerely
Pim
_________________________________________________________________
Jouw nieuws en entertainment, vind je op MSN.nl!
http://nl.msn.com/
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
