Differences in Results

Users who run analyses in both modes may see slight differences in the results between IBM® SPSS® Modeler and IBM SPSS Modeler Server. The discrepancy usually occurs because of record ordering or rounding differences.

Record ordering. Unless a stream explicitly orders records by sorting them, the order in which records are presented may vary between streams executed locally and those executed on the server. There may also be differences in order between operations run within a database and those run in IBM SPSS Modeler Server. These differences are due to the different algorithms used by each system to implement functions that may reorder records, such as aggregation. Also, note that SQL does not specify the order in which records are returned from a database in cases where there is no explicit ordering operation.

Rounding differences. IBM SPSS Modeler running in local mode uses a different internal format for storing floating point values than does IBM SPSS Modeler Server. Due to rounding differences, results might vary slightly between each version.