topic Proc Compare: Equal values showing up in differences output in SAS Procedures

Proc Compare: Equal values showing up in differences output

Huey — Fri, 06 Apr 2012 18:41:52 GMT

Hi All,

I have come across a strange situation where a numeric variable is zero in both the base and compare datasets, on the matching ID, and yet they are showing up in the differences output. Below is how I've set up the compare code:

proc compare base = work.base_ds

compare = work.compare_ds

listobs listvar maxprint=(25,3000) ;

ID InternalID notsorted;

attrib _ALL_ label=''; /*Get rid of labels, formats and informats for comparison.*/

format _ALL_ ;

informat _ALL_ ;

run;

Below is an example of the results:

_______________________________________________________________

|| Base Compare

InternalID || Score Score Diff. % Diff

____________ || _________ _________ _________ _________

8329 || 0 0 0 0

8331 || 0 0 0 0

Any ideas?

Thanks,

Huey

Re: Proc Compare: Equal values showing up in differences output

data_null__ — Fri, 06 Apr 2012 20:42:25 GMT

Format SCORE with the HEX16. format. You should see a difference perhaps in the last digit.

Re: Proc Compare: Equal values showing up in differences output

ballardw — Fri, 06 Apr 2012 21:43:38 GMT

Or try the FUZZ= option. They are probably displaying as equal because of the format an may vary by a small amount.

If your data is such that a diference such as 1e-8 is "close enough to equal" try FUZZ= 1E-8 (OR 0.00000001) or other small value.

Differences smaller than your FUZZ value will be considered equal.

Re: Proc Compare: Equal values showing up in differences output

Huey — Fri, 06 Apr 2012 22:16:22 GMT

Thanks for the input ballardw, but the "difference" still shows up when I use your fuzz factor setting, even when I use a very fuzzy factor (0.001) the "difference" still shows. : |

Re: Proc Compare: Equal values showing up in differences output

Huey — Fri, 06 Apr 2012 22:35:51 GMT

This is yielding interesting/aggrevating information. Representing the fields in HEX16. format shows that:

Base - Score = 0000000000000000

Compare - Score = 0

So, after wondering how on earth one '0' was popping up, I finally realized that I had the MISSING='0' option set!!!

I was comparing a missing value to '0' without knowing it. The HEX format really brought that to life. Thank you.

This option was buried in my process control file, and was hard to locate. Please forgive me for wasting your time!