looks like MODE statistic is only supported by PROC UNIVARIATE [check Keywords and Formulas, Simple Statistics in SAS Elementary Statistics Procedures, SAS Online Doc]

your PROC SUMMARY code generated error on my machine: Unix SAS 9.1 64-bit

Are u using SAS 9.2? If so, maybe SAS output missing because this statistic is not supported in this procedure.

On Fri, 9 Jul 2010 09:38:19 -0400, Mike Zdeb <msz03@ALBANY.EDU> wrote:

>hi ...just saw this and thought I'd offer another idea ... > >by the way ... if a group has only one member (as in one formed with a >CLASS or BY statement), PROC MEANS (and SUMMARY) return a MISSING value >for the MODE, but PROC UNIVARIATE returns a real value > >shouldn't they be consistent ??? > >***************************************** >data x; >input datasource brand : $10. quarter : $6. sale; >datalines; > 1 toyota 1977q1 15 > 1 toyota 1977q2 25 > 1 toyota 1977q3 35 > 1 ford 1977q1 45 > 1 ford 1977q2 55 > 1 ford 1977q3 65 > 2 toyota 1977q1 15 > 2 toyota 1977q2 25 > 2 toyota 1977q3 99 > 3 toyota 1977q3 99 >; >run; > >* compute mode and mean for each brand and quarter; >proc summary data=x nway; >class brand quarter; >var sale; >output out=modes (drop=_:) mode=mode mean=mean; >run; > >* compare mode to each sale within brand/quarter; >proc sort data=x; >by brand quarter; >run; > >data y; >do until (last.quarter); > merge x modes; > by brand quarter; > if mode eq . then mode = mean; > different = sum(different,(sale ne mode)); >end; >conflict_flag = (different gt 0); >keep conflict_flag brand quarter mode; >run; > >proc print data=y; >run; > > > >-- >Mike Zdeb >U@Albany School of Public Health >One University Place (Room 119) >Rensselaer, New York 12144-3456 >P/518-402-6479 F/630-604-1475 > >On Jul 7, 5:08 pm, hewei2004 <hewei2...@gmail.com> wrote: >> Hi, >> >> Suppose that I have the following file >> >> datasource brand quarter sale >> 1 toyota 1977q1 15 >> 1 toyota 1977q2 25 >> 1 toyota 1977q3 35 >> 1 ford 1977q1 45 >> 1 ford 1977q2 55 >> 1 ford 1977q3 65 >> 2 toyota 1977q1 15 >> 2 toyota 1977q2 25 >> 2 toyota 1977q3 99 >> 3 toyota 1977q3 99 >> >> I want to create a file that merges the information in datasource=1 >> and datasource=2 and datasource=3, and create a variable called >> conflict_flag when datasource1 or datasource2 or datasource3 >> disagrees. >> >> note that datasource=1 agrees with datasource=2 agrees on 1977q1 and >> 1977q2, thus conflict_flag=0 >> note that datasource=1 agrees with datasource=2 disagrees on 1977q3, >> thus conflict_flag=1 >> >> The desired output is: >> conflict_flag brand quarter sale >> 0 toyota 1977q1 15 >> 0 toyota 1977q2 25 >> 1 toyota 1977q3 [mode of (35, 99, 99 ), which is 99 of >> course] >> 0 ford 1977q1 45 >> 0 ford 1977q2 55 >> 0 ford 1977q3 65