LDALY@IRLEARN.BITNET (LESLIE DALY PhD) (01/31/90)
Lisa King <LMJY@CORNELLA.BITNET> had a query re TABULATE when it produced two different sets of answers with the following two sets of code: PROC TABULATE; PROC TABULATE; CLASS V10A V28; AND CLASS V10A V10B V28; TABLE V10A,V28; TABLE V10A V10B,V28; The answers differed in the part of the table giving N of V10A by V28. The reason is that V10B is a CLASS variable that has missing values for 2 observations where V10A is valid. In the first case the TABULATE is correct and gave what was expected. In the second case the *observations* with the missing values were omitted from ALL tables requested. 'A missing value in a class variable causes the observation to be ignored' Basics manual p 1098. This happens even if the particular class variable does not form part of the crosstabulation (to borrow SPSS terminology) in question. I have always found this to be a bit of a bother but I think there are good reasons for it in terms of consistency of table results. -------------------------------------------------------------------- Leslie Daly Ph.D. (Sex: male!) Telephone: +353-1-693244 ext 6315 Lecturer in Biostatistics, Network: LDALY@IRLEARN.BITNET Department of Community Medicine and Epidemiology, University College Dublin, Earlsfort Terrace, Dublin 2 IRELAND. --------------------------------------------------------------------