SPSS® 12.0 Command Syntax Reference

Subcommand Order
Syntax Rules
Operations
Limitations
Example
• Subcommands can be specified in any order.
EXSMOOTH 537
• VARIABLES can be specified only once.
• Other subcommands can be specified more than once, but only the last specification of
each one is executed.
• The value list for subcommand SEASFACT and the grid values for the smoothing parameters
must be enclosed within parentheses.
• If a smoothing parameter is specified for an inappropriate model, it is ignored (see
“Smoothing Parameter Subcommands” on p. 541).
• EXSMOOTH cannot process series with missing observations. (You can use the RMV command
to replace missing values, and USE to ignore missing observations at the beginning
or end of a series. See RMV and USE in the SPSS Syntax Reference Guide for more information.)
• When EXSMOOTH is used with PREDICT, error series are assigned the system-missing
value in the entire PREDICT range. The original series is system-missing beyond the last
original case if the series is extended. (See the SPSS Syntax Reference Guide for more information
on PREDICT.)
• Maximum 1 VARIABLES subcommand. There is no limit on the number of series named
on the list.
• Maximum 1 model keyword on the MODEL subcommand.
EXSMOOTH VAR2
/MODEL=LN
/ALPHA=0.2.
• This example specifies a linear trend, nonseasonal model for the series VAR2.
• The ALPHA subcommand specifies a value of 0.2 for the general smoothing parameter.
• The default value of 0.1 is used for gamma.