cap prog drop myreg2

program define myreg2

	version 8

	args lnf theta1 theta2 

	quietly replace `lnf'= -($ML_y1-`theta1')^2/(2*`theta2'^2)-0.5*ln(`theta2'^2)

end

ml model lf myreg2 (reg:y=x1 x2) /sigma

ml maximize