title: Stata Weighted Least Squares Regression
body: <p>I realize this may be a novice question, but I'm still a beginner with Stata.  I have a dataset that I'm trying to run a weighted least squares regression on, and I've installed the wls0 package.  However, when I try to run my regression, I get a strange error:</p>
  
  <p>option wvars() required
  r(198);</p>
  
  <p>This doesn't happen when I try to run a regression for an example dataset used in a wls0 tutorial.  Does anyone know anything about this?</p>