st: DEA command in Stata, error message

[Alberto Zaffaroni - 1338011 <alberto.zaffaroni@studbocconi.it>]

Hello, 

I am a MSc student at Bocconi University. 
I am writing my Master thesis and in order to complete data analysis I need to run the DEA (Data Envelopment Analysis) command using a dataset of input and output measures that I created. 
I have the dea.ado file installed in the directory on which Stata operates and everything seems to be ready to work. 
Unfortunately, when I try to run the DEA command, this error message is the only result: 


lp_phase2(): 3498 No Solution at Stage 1 and Phase 2.:[DMUi=1] 
_dealp(): - function returned error 
<istmt>: - function returned error 
r(3498); 

Can anybody help me trying to understand what's going on and what's the problem, please? 
I have looked for solutions everywhere but could not find any. 


Thanks in advance for your kind attention. 





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