topic Re: ODS output in SAS Programming

ODS output

mt88 — Thu, 25 Apr 2024 15:01:55 GMT

Hello,

I used the following code...

ods output chisq=tst;
proc freq data = combinedIDmanu;
tables fentanyl*num_doc_vis_catB/chisq;
run;

to send this results table:

Statistic	DF	Value	Prob
Chi-Square	2	0.9499	0.6219
Likelihood Ratio Chi-Square	2	1.7052	0.4263
Mantel-Haenszel Chi-Square	1	0.3486	0.5549
Phi Coefficient		0.0812
Contingency Coefficient		0.081
Cramer's V		0.0812
WARNING: 50% of the cells have expected counts less than 5. Chi-Square may not be a valid test.

to a dataset with the following fields:

Table	Statistic	DF	Value	Prob
Table fentanyl * num_doc_vis_catB	Chi-Square	2	0.9499	0.6219
Table fentanyl * num_doc_vis_catB	Likelihood Ratio Chi-Square	2	1.7052	0.4263
Table fentanyl * num_doc_vis_catB	Mantel-Haenszel Chi-Square	1	0.3486	0.5549
Table fentanyl * num_doc_vis_catB	Phi Coefficient	_	0.0812	_
Table fentanyl * num_doc_vis_catB	Contingency Coefficient	_	0.081	_
Table fentanyl * num_doc_vis_catB	Cramer's V	_	0.0812	_

Is there a way to use the ods statement so that this part of the results table:

WARNING: 50% of the cells have expected counts less than 5. Chi-Square may not be a valid test.

is added to the dataset?

Thank you.

Re: ODS output

ballardw — Fri, 26 Apr 2024 13:52:45 GMT

SAS doesn't appear to expose that message to ODS output.

If I had to do such I would also output the crosstabfreqs such as:

ods output chisq=tst
           crosstabfreqs=freqs;

Then summarize the small cell counts:

Proc format library=work;
value _5freq
0-<5= '<5'
5<-high ='5+'
;
proc freq data=freqs;
   /* this where for a simple example like this 
   gets the cells from the  body of the table
   */
   where _type_='11';
   tables frequency /out=freqpct;
   format frequency _5freq.;
run;

and use that Freqpct data to create whatever you think should be added to that Chi square result set.

Re: ODS output

FreelanceReinh — Thu, 25 Apr 2024 15:37:42 GMT

Hello @mt88,

You could use PROC SQL to add a constant variable to the ODS output dataset containing the percentage of cells with expected frequency less than 5:

ods output chisq=tst crosstabfreqs=ctf;
proc freq data = combinedIDmanu;
tables fentanyl*num_doc_vis_catB/chisq expected;
run;

proc sql;
create table want as
select * 
from tst, (select mean(.<expected<5) as expected_lt_5 format=percent6.0
           from ctf
           where _type_='11');
quit;