01-01-2014 08:13 PM
I have a macro that successfully creates 2x2 contingency tables, one for each value of a variable X. The contingency tables are created from PROC FREQ.
Now, I would like to
1) calculate the specificity and sensitivity from each table
2) plot all pairs of sensitivity and 1-specificity to create an ROC curve (sensitivity vs. 1-specificity) for all values of X
Is there a way to automate this in SAS? I can't find a way to do so via searching on Google or SAS documentation.
I envision the successful macro being able to
a) extract the counts from each cell in each contingency table
b) calculate sensitivity and 1-specificity for each contingency table
c) plot sensitivity vs. 1-specificity
but I can't figure out how to do this. (I'm sure that DO-loops and arrays are needed somehow.)
Thus, right now, I am typing the counts by hand into Microsoft Excel and plotting the ROC curve there. This worked initially when I only had to create 5 ROC curves, but I now need to produce 20, and I wish to automate this process.
Any help that you can provide would be much appreciated!
01-01-2014 10:04 PM
You might post this in the SAS/Graph and ODS Graphics forum. This paper/presentation, for example, shows a method using the SG procedures from data that seems to be generated with PROC FREQ