I am running:
ods graphics on;
proc irt data=ff1 RESFUNC=graded plots=iic;
var fv_preptime fv_fresh fv_prepknow fv_filling fv_restarauntserv fv_sugar fv_dontlook fv_costtoomuch;
run;
ods graphics off;
on data that has 5 categories (ie. never, rarely, neutral, often, and always). I am trying to get IIC plots, not ICC plots, but I keep getting an error:
NOTE: The IRT procedure is experimental in this release of the SAS system.
103 proc irt data=ff1 RESFUNC=graded plots=iic;
---
1
WARNING 1-322: Assuming the symbol ICC was misspelled as iic.
I have run it other ways including plots=all, plots=(scree(unpack) iic) and I just can't seem to get the IIC plots.
Any suggestions?
Thanks!
Try it on a simple example. Perhaps there is something degenerate about your data:
data IrtUni;
input item1-item8 @@;
datalines;
1 0 0 0 1 1 2 1 1 1 1 1 1 3 3 3 0 1 0 0 1 1 1 1 1 0 0 1 0 1 2 3 0 0 0
0 0 1 1 1 1 0 0 1 0 1 3 3 0 0 0 0 0 1 1 3 0 0 1 0 0 1 2 2 0 1 0 0 1 1
3 3 0 1 0 0 1 2 2 1
;
proc irt data=IrtUni plots=ICC;
var item1-item8;
run;
Hi Rick,
Thank you for your response! I just ran what you posted and changed plots=IIC and I still got this error:
237 proc irt data=IrtUni plots=IIC;
---
1
WARNING 1-322: Assuming the symbol ICC was misspelled as IIC.
Any other thoughts as to why it doesn't like IIC?
My data is 5 categories (strongly agree=1, agree=2, neutral=3, disagree=4, and stronlgy disagree=5).
Thank you!
The IIC plot was introduced in SAS/STAT 13.2. (13.2 = SAS 9.4m2) I conjecture that you are running 13.1 and so that plot is not available. You can check your SAS version by using
%put SYSVLONG = &SYSVLONG;
I have SYSVLONG = 9.04.01M1P120413
Right, and the M1 means you are running SAS 9.4m1 = SAS/STAT 13.1. There have been three releases of SAS since then (13.2, 14.1, and 14.2).
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