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Building CLEM Expressions

About CLEM

The Control Language for Expression Manipulation (CLEM) is a powerful l anguage for analyzing
and manipulating the data that flows along IBM® SPSS® Modeler streams. Data miners use
CLEM extensively in stream operations to perform tasks as simple as deriving profit from cost
and revenue data or as complex as transforming web log data into a set of fields and records with
usable information.
CLEM is used within SPSS Modeler to:
Compare and evaluate conditions on record fields.
Derive values for new fields.
Derive new values for existing fields.
Reason about the sequence of records.
Insert data from records into reports.
Scripting. A subset of the CLEM language can also be used when scripting in the user interface.
This allows you to perform many of the same data manipulations in an automated fashion.
CLEM expressions are indispensable for data preparation in SPSS Modeler and can be used in
a wide range of nodes—from record and field operations (Select, Balance, Filler) to plot san d
output (Analysis, Report, Table). For example, you can use CLEM in a Derive node to create a
new field based on a formula such as ratio.
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