* open log file
log using class_size_1.log, replace

* open class_size_1, 420 observations from 
* california k-6 and k-8 schools
* 6th grad test scores
use ca_school_data_2

* get means of key variables
sum average_score student_teacher esl_pct

* get correlations between key variables
corr average_score student_teacher esl_pct

* run regression with one variable
reg average_score student_teacher

* run synthetic regression of esl_pct on 
* student_teacher
reg esl_pct student_teacher

* run multivariate regression
reg average_score student_teacher esl_pct


* demonstrate the partialing out
* nature of mv regressions

* run a regression of STR on ESL
* output the residuals
reg student_teacher esl

* output residuals
predict res_str, residual

* run a regression of test scores
* on the student_teacher residuals
reg average_score res_str


* close log file
log close
* see ya