topic Re: Proc Freq issues in SAS Procedures

Proc Freq issues

Doug____ — Wed, 03 Oct 2018 16:32:07 GMT

I created a dataset with all possible combinations of subgroup variables for a binary response. However, no subjects had a response value so PROC FREQ returns the following:

A row or column sum is zero for the table

I thought I could get around this by using PROC MEANS to fill all the zero response rows with zeros then use the WEIGHT count/zeros option in FREQ but it does not work. I'm trying to compute CIs for the binomial proportions. Any thoughts?

Example Data

Treat Var Count

Test Yes 0

Test No 100

Control Yes 0

Control No 100

Re: Proc Freq issues

ballardw — Wed, 03 Oct 2018 16:36:48 GMT

Doesn't work is awful vague.

Are there errors in the log?: Post the code and log in a code box opened with the {i} to maintain formatting of error messages.

No output? Post any log in a code box.

Unexpected output? Provide input data in the form of data step code pasted into a code box, the code you used, the actual results and the expected results if possible. Instructions here: https://communities.sas.com/t5/SAS-Communities-Library/How-to-create-a-data-step-version-of-your-dat... will show how to turn an existing SAS data set into data step code that can be pasted into a forum code box using the {i} icon or attached as text to show exactly what you have and that we can test code against.

Re: Proc Freq issues

Doug____ — Wed, 03 Oct 2018 16:43:19 GMT

proc freq data = counts ;

where subgroupan = 1; <<<<-several subgroups does not matter which one

table trtpn*ev /out = x /*binomial riskdiff exact alpha = 0.1*/ outpct ;

weight count/zeros;

*ods output riskdiffcol2 = rd2;

run;

WARNING: Output 'riskdiffcol2' was not created. Make sure that the output object name, label, or path is spelled correctly. Also,

verify that the appropriate procedure options are used to produce the requested output object. For example, verify that

the NOPRINT option is not used.

Re: Proc Freq issues

ballardw — Wed, 03 Oct 2018 17:01:50 GMT

@Doug____ wrote:

proc freq data = counts ;

where subgroupan = 1; <<<<-several subgroups does not matter which one

table trtpn*ev /out = x /*binomial riskdiff exact alpha = 0.1*/ outpct ;

weight count/zeros;

*ods output riskdiffcol2 = rd2;

run;

WARNING: Output 'riskdiffcol2' was not created. Make sure that the output object name, label, or path is spelled correctly. Also,

verify that the appropriate procedure options are used to produce the requested output object. For example, verify that

the NOPRINT option is not used.

Your "example data" in the first post does not include any variables name subgroupan trtpn or ev. So again, I request example data that causes the error.

It is very easy to make a small data set with data step code. From your "example data"

data have;
   input Treat  $         Var $            Count;
datalines;
Test           Yes                 0
Test           No                 100
Control      Yes                   0
Control       No                100
;
run;

The $ are used to read character values.

Re: Proc Freq issues

Doug____ — Wed, 03 Oct 2018 17:04:55 GMT

this is the example that causes the problem because there are no "yes" responses to FREQ does not calculate any CIs for the difference and returns a warning to the log.

Re: Proc Freq issues

ballardw — Wed, 03 Oct 2018 17:48:22 GMT

@Doug____ wrote:

this is the example that causes the problem because there are no "yes" responses to FREQ does not calculate any CIs for the difference and returns a warning to the log.

From what you have shown so far we can't get to that stage. You have not shown values for any of the variables on the tables statement. So the only thing I can get is errors about missing variables.

Either provide data that matches the Proc Freq or provide proc freq that matches the data.

Re: Proc Freq issues

Doug____ — Wed, 03 Oct 2018 17:55:00 GMT

AGE1	<55	Control	No	160
AGE1	<55	Control	Yes	0
AGE1	<55	Test	No	141
AGE1	<55	Test	Yes	0
AGE1	>=55	Control	No	98
AGE1	>=55	Control	Yes	0
AGE1	>=55	Test	No	113
AGE1	>=55	Test	Yes	0

These are the summary count data being fed into proc freq

Re: Proc Freq issues

ballardw — Wed, 03 Oct 2018 18:00:37 GMT

@Doug____ wrote:

AGE1

<55

Control

No

160

AGE1

<55

Control

Yes

0

AGE1

<55

Test

No

141

AGE1

<55

Test

Yes

0

AGE1

>=55

Control

No

98

AGE1

>=55

Control

Yes

0

AGE1

>=55

Test

No

113

AGE1

>=55

Test

Yes

0

These are the summary count data being fed into proc freq

And which variable is which in the Proc Freq code you showed? And that is not a data step and I am not going to clean up that format to make one.

Re: Proc Freq issues

Doug____ — Wed, 03 Oct 2018 20:33:33 GMT

Freq uses the count variable on the right with a weight statement. So the analysis is for each subgroup is the treatment (Control /Test) * the count variable. Then use the weight variable to get the percentages. Basically you can use the first two rows to run Freq since it is summary data. I was using Freq to get the CIs for the difference but it won't give those since there are no responses (everything is "No").

Re: Proc Freq issues

Reeza — Wed, 03 Oct 2018 22:13:35 GMT

For 0 values try using the EXACT statement with PROC FREQ. You may also want to look into the ZEROS option.

https://communities.sas.com/t5/SAS-Procedures/Proc-Freq-All-inclusive-table/td-p/202542

Not sure if it’ll work for the CI but should appear in the table at least.

And another option that’s handy is the SPARSE option.

@Doug____ wrote:

Freq uses the count variable on the right with a weight statement. So the analysis is for each subgroup is the treatment (Control /Test) * the count variable. Then use the weight variable to get the percentages. Basically you can use the first two rows to run Freq since it is summary data. I was using Freq to get the CIs for the difference but it won't give those since there are no responses (everything is "No").

Re: Proc Freq issues

Doug____ — Thu, 04 Oct 2018 13:40:38 GMT

I am using weight/zeros already which from the documentation invokes the SPARSE option - the warning still appears.