how intercept is calculated

[momi]

Hi,

Does anyone know how intercept is calculated in PROC REG or PROC SURVEYERG when weight is assigned?  Is it calculated as a weighted mean of outcome?  Or is weighted ignored?

Thank you,

Momi

[data_null__]

proc glm data=sashelp.class;
   weight age;
   model weight= / solution;
   run;
proc means data=sashelp.class;
   weight age;
   var weight;
   run;