topic Re: Create least squares line of Y on X separately for a dichotomous variable in SAS Programming

Create least squares line of Y on X separately for a dichotomous variable

aespinarey — Fri, 13 Jul 2018 03:32:33 GMT

Hello,

I am having trouble finding a way to obtain the least squares line of PIC (Y) on YNG (X) separately for a dichotomous variable.

Latin America: Y= B1 +B2X

Africa: Y= B1 + B2X

This is the code I am using, but I doubt I am getting the right results:

data q2;
set work.ch12q02;
run; proc print;run;

proc glm data=q2;
class COUNTRY;
model PCI=YNG COUNTRY / solution;
lsmeans COUNTRY;
run; proc print; run;

Output:

Please help,

Thank you!

Re: Create least squares line of Y on X separately for a dichotomous variable

pau13rown — Fri, 13 Jul 2018 04:13:52 GMT

interaction, so you have separate slopes for each country:

proc glm data=q2;
class COUNTRY;
model PCI=country YNG*COUNTRY / solution;
lsmeans COUNTRY;
run;

or use a where statement to subset:

proc glm data=q2 (where=(country="XXXX"));
model PCI=YNG/ solution;

lsmeans YNG;
run;

Re: Create least squares line of Y on X separately for a dichotomous variable

PGStats — Fri, 13 Jul 2018 05:07:27 GMT

The intercept and slope estimates will be given directly by:

/* Common error variance */

proc glm data=ch12q02;
class country;
model pci = country country*yng / noint solution;
run;

/* or, separate error variance for each country */

proc glm data=ch12q02;
by country notsorted;
model pci = yng / solution;
run;