In reply to surachai.

I have three suggestions:
1. On the PROC LOGISTIC statement, specify
proc logistic data=Data1 plots=(effectplot roc);
PROC LOGISTIC will automatically create the graphs you want.
2. To ask questions like this, post your code and question to the SAS Support Community for Statistical Procedures.
3. When creating graphs in SAS, consider using the newer SGPLOT procedure instead of the older GPLOT procedure.