Hello,
I want to have in the output for a Cox regression (the table with the results for the estimates for maximum likelihood analysis) the list showing the results for each level of the independent variable "independent_v1" or "independent_v2".
My dataset is like this:
data have;
input
id time1 event1 weight independent_v1 independent_v2;
datalines;
1 0 0 0.8 0 1
1 1 0 0.8 0 1
1 2 0 0.8 0 0
1 3 0 0.8 0 0
1 4 0 0.8 0 1
15 0 0.8 0 1
1 6 0 0.8 0 1
1 7 0 0.8 0 1
1 8 0 0.8 0 2
1 9 0 0.8 0 2
1 10 0 0.8 0 2
1 11 0 0.8 0 2
1 12 0 0.8 0 2
1 13 0 0.8 0 2
2 0 0 1.1 1 0
2 1 1 1.1 1 0
2 2 . 1.1 1 0
3 0 0 1.01 2 1
3 1 0 1.01 2 1
3 2 1 1.01 2 1
3 3 . 1.01 2 1
4 0 1 0.98 2 1
4 1 . 0.98 2 1
4 2 . 0.98 2 1
4 3 . 0.98 2 1
4 4 . 0.98 2 1
5 0 0 1.13 3 0
6 0 0 1.05 3 0
6 1 0 1.05 3 1
6 2 0 1.05 3 1
6 3 0 1.05 3 1
6 4 0 1.05 3 1
6 5 1 1.05 3 1
6 6 . 1.05 3 1
6 7 . 1.05 1 1
6 8 . 1.05 1 1
7 0 0 0.89 0 3
7 1 0 0.89 0 3
7 2 0 0.89 0 3
7 3 0 0.89 0 3
7 4 0 0.89 0 3
7 5 0 0.89 0 3
7 6 0 0.89 0 3
7 7 0 0.89 0 3
7 8 1 0.89 0 1
7 9 . 0.89 0 1
7 10 . 0.89 0 1
8 0 0 1.1 1 0
8 1 0 1.1 1 1
8 2 0 1.1 1 1
8 3 . 1.1 1 2
8 4 . 1.1 1 2
;
run;
When I code I have the regression results list, but I would like to know how to change the reference category for each independent variable.
My coding:
proc phreg data=have;
class independent_v1 independent_v2;
id id;
model time1*event1(0) = independent_v1 independent_v2;
weight weight;
run;
So SAS automatically chooses to omit one level as the reference category for each independent variable. For example, How I could change that so I choose the reference category 1 for "independent_v1" and 3 for "independent_v2", ?
Thanks for the help!