During the compilation
phase, the program data vector is created. The program data vector
includes the two automatic variables _N_ and _ERROR_. The descriptor
portion of the new SAS data set is created at the end of the compilation
phase. The descriptor portion includes the name of the data set, the
number of observations and variables, and the names and attributes
of the variables. Observations are not written until the execution
phase.
Correct answer: a
Syntax checking can
detect many common errors, but it cannot verify the values of variables
or the correctness of formats.
Correct answer: c
The DATA step executes
once for each record in the input file, unless otherwise directed.
Correct answer: d
The remaining variables
are initialized to missing. Missing numeric values are represented
by periods, and missing character values are represented by blanks.
Correct answer: b
The default value of
_ERROR_ is 0, which means there is no data error. When an error occurs,
whether one error or multiple errors, the value is set to 1.
Correct answer: d
By default, at the end
of the DATA step, the values in the program data vector are written
to the data set as an observation, control returns to the top of the
DATA step, the value of the automatic variable _N_ is incremented
by one, and the values of variables that were created in programming
statements are reset to missing. The automatic variable _ERROR_ is
reset to 0 if necessary.
Correct answer: a
The order in which variables
are defined in the DATA step determines the order in which the variables
are stored in the data set.
Correct answer: c
When SAS cannot detect
syntax errors, the DATA step compiles, but it does not execute.
Correct answer: a
A semicolon is missing
from the second line. It will cause an error because the INPUT statement
will be interpreted as an invalid INFILE statement option.
Correct answer: d
The third line of the
log displays the value for IDnum, which is clearly a character value.
The fourth line displays the values in the program data vector and
shows a period, the symbol for a missing numeric value, for IDnum.
The other values are correctly assigned. Thus, it appears that numeric
values were expected for IDnum. A dollar sign, to indicate character
values, is missing from the INPUT statement.