st: "no observations" in kernel regression

[Raul Andrade <andrade@wueconc.wustl.edu>]

Hello all.
I have a quick question.
I am trying to run a kernel regression between variables y (dependent) 
and x (independent).
I downloaded and installed the program for the command kernreg from the 
Stata help file, and I am doing the following:

kernreg yvar xvar, kercode(6) bwidth(0.65) npoint(100)

As a result I receive the following message:

no observations.

I thought it had to do something with the missing values, so, to 
experiment, I kept only those observations without missing values and 
tried to run the kernel regression again. The same message appeared.

Does anybody has a clue about why this is happening and how to solve 
this problem?

Thanks for your help.

Raul Andrade


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