不是让你看帮助了吗,严格按照帮助的例子。
你看看人家的dmu变量是怎么设置的。你的是怎么设置的。
help malmq
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Title
malmq -- Malmquist Productivity Index using DEA frontier in Stata
Syntax
malmq ivars = ovars , {period}[if] [in] [, options]
options Description
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Main
ort(string) specifies the orientation. The default is ort(i), meaning the input oriented distance Data
Envelopment Analysis(DEA) frontier used. ort(out) means the output oriented DEA frontier.
trace lets all the sequences and results displayed in the result window be saved in the "malmq.log"
file.
saving(filename) specifies that the results be saved in filename.dta. If the filename already exists, the
previous filename will be saved with the name of filename_bak_DMYhms.dta.
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Description
malmq selects the input and output variables from the user designated data file or in the opened data set and solves
Malmquist Productivity Index using Data Envelopment Analysis(DEA) frontier by options specified.
The malmq program requires initial panel data set that contains the input and output variables and period for observed
units.
Variable names must be identified by ivars for input variable, by ovars for output variable, and by period for panel
period of time to allow that malmq program can identify and handle the multiple input-output data set. And the
variable name of Decision Making Units(DMUs) is to be specified by "dmu".
sav(filename) option creates a filename.dta file that contains the results of malmq including the informaions of the
DMU, input and output data used, efficiency change, technology change, total factor productivity change, scale
efficiency change, and pure technical change.
The log file, malmquist.log, will be created in the working directory.
Examples
. input str20 dmu year o_q i_x
dmu year o_q i_x
1. firm1 2009 1 2
2. firm2 2009 2 4
3. firm3 2009 3 3
4. firm4 2009 4 5
5. firm5 2009 5 6
6. firm1 2010 1 2
7. firm2 2010 3 4
8. firm3 2010 4 3
9. firm4 2010 3 5
10. firm5 2010 5 5
11. firm1 2011 1 2
12. firm2 2011 3 4
13. firm3 2011 4 3
14. firm4 2011 3 5
15. firm5 2011 5 5
16. end
. malmq i_x = o_q,period(year)
. malmq i_x = o_q,ort(o) period(year)
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