Question

Which subsetting IF statement selects observations for subsequent processing only if all three input data sets contribute to the current observation?

data merged.flowers;
merge (rename=(red=BrickRed) in=yellow)
(in=purple)
spring.petunias(in=pink);
by ID;
_________________________
run;
a. if yellow=1 and purple=1 or pink=1;
b. if yellow=0 or purple=0 or pink=0;
c. if yellow=1 and purple=1 and pink=1;
d. if yellow=1 or purple=1 and pink=0;

Answer 1

The correct subsetting IF statement that selects observations only if all three input datasets contribute to the current observation in SAS is: 'if yellow=1 and purple=1 and pink=1;'. This ensures that the observation is present in the merged dataset from each of the three sources, which are indicated by the in= option flags.

Step-by-step explanation:

The question pertains to SAS programming, specifically the process of subsetting data when performing a merge of multiple datasets. In SAS, the in= option is used to create a binary flag that indicates whether a particular dataset contributes to the observation in a merged dataset.

In this scenario, the correct IF statement to select observations for subsequent processing only if all three input datasets contribute to the current observation is:

c. if yellow=1 and purple=1 and pink=1;

The other options provided would either select observations that do not have contributions from all three datasets or exclude observations based on other conditions. Therefore, option C is the one that ensures all three datasets (now called BrickRed, purple, and spring.petunias with a flag of pink) are present in the merged dataset.