SPSS® 12.0 Command Syntax Reference

VARSTOCASES 1653
• The basic specification is /INDEX=ivar(n) ivar(n) ..., where ivar is the name of the new
index for a factor and n is the number of factor levels represented in the variable group
for which the index is being constructed.
• The last index specified varies the fastest.
Example
B1 B2
A1 .00 .05
A2 5.00 3.00
• Data were collected for a designed experiment with two levels of factor A and two levels
of factor B. The table shows the data for the first case.
caseid v_a1b1 v_a1b2 v_a2b1 v_a2b2
001 .00 .05 5.00 3.00
• The original data file is structured so that each case has one variable for each combination
of factors. Note that factor B varies fastest.
VARSTOCASES
/MAKE newvar FROM v_a1b1 TO v_a2b2
/INDEX=a(2) b(2).
caseid a b newvar
001 1 1 .00
001 1 2 .05
001 2 1 5.00
001 2 2 3.00
• The command restructures the data file and creates two indices, A and B.
NULL Subcommand
The NULL subcommand checks each potential new row for null values. A null value is a
system-missing or blank value. By default, VARSTOCASES does not add a new row that
contains null values for all variables created by MAKE subcommands. You can change the
default null-value treatment with the NULL subcommand.
DROP Do not include a new row when all MAKE variables are null. A potential new row
with null values for all of the variables created by MAKE subcommands is excluded
from the new data file. This is the default.
With this option, you may want to create a count variable to keep track of new rows,
because cases in the original data file are not guaranteed to appear in the new data
file.
KEEP Include a new row when all MAKE variables are null. A potential new row with
null values for all of the variables created by the MAKE subcommand is included in
the new data.
With this option, you may not need a count variable to keep track of cases because
each row in the original data will result in a consistent number of rows in the new
data file.