* create data and graph regression example
clear
set seed 315
set obs 34
gen y = (uniform()*4) in 1/30
gen x = (4 - (y)) + (uniform()) in 1/30
* change one point
replace y = 9 in 31
sum x
sca meanx = r(mean)
replace x = meanx in 31
* compute the regression
reg y x
* change two points
replace x = 0 in 32
replace x = 5 in 33
* compute predictions
predict yhat 
predict res , res
list if y > 5
graph twoway (scatter y x) /// draw a scatter plot of y vs. x
    (line yhat x), // draw predicted y vs. x
graph export 02rgraph1.eps, replace 

graph twoway (scatter y x) /// draw a scatter plot of y vs. x
    (line yhat x) /// draw predicted y vs. x
    (scatter res x, yaxis(2)) ///  draw scatter plot res vs. x with
    (scatteri 9 2.45268 "observation 31", ///
    msymbol(i) yvarlabel(" ") )
graph export 02rgraph2.eps, replace