New R Extension for IBM SPSS Statistics: Travelling Salesperson Problem

This extension uses the TSP package in R to solve the traveling salesperson optimization problem. The extension supports both symmetric and asymmetric costs (distances). In what follows, the term node is used to represent the points or locations to be included in the optimization problem and the term cost describes the distance or generalized distance...  Continue reading New R Extension for IBM SPSS Statistics: Travelling Salesperson Problem

Using SPSSINC PROGRAM and generalizing your code vs writing macros in SPSS Statistics

Suppose you want to generate all two-way crosstabs for a set of variables in your dataset but without creating any of the redundant transposed tables (V2 BY V1 and V1 by V2). You could, of course, write a lot of CROSSTABS commands, but that would be very tedious and error prone. You could...  Continue reading Using SPSSINC PROGRAM and generalizing your code vs writing macros in SPSS Statistics

Getting the Most of the Extension Commands on the SPSS Community Site

The SPSS Community website has a wealth of resources for users of SPSS Statistics and other SPSS products. In particular, there are many extension commands you can download and use for free. Extension commands typically consist of a dialog box interface, traditional SPSS syntax, and an implementation in Python or R.   Continue reading Getting the Most of the Extension Commands on the SPSS Community Site

Case Control Matching with the FUZZY Extension command

Case-control matching is a popular technique used to pair records in the "case" sample with similar records in a typically much larger "control" sample based on a set of key variables. This post discusses the FUZZY extension command for SPSS Statistics that implements this technique and some recent enhancements to it.  Continue reading Case Control Matching with the FUZZY Extension command