SPSS
SPSS is both a static-typed, interpreted programming language and a proprietary application used to run programs written in SPSS. PSPP is a free and open-source implementation of the interpretter.
SPSS and PSPP
IBM has owned SPSS since version 16 and has done their best to erase older versions from history. IBM has also erased the headless mode of operation. Official support and online documentation is only available for versions 25 and later. Beyond that, a user manual in PDF format is distributed with the SPSS application.
PSPP is a GNU project to create a free and open-source application that can run programs written in the SPSS language. The PSPP project fully supports headless operation.
Installing PSPP
Many Linux and BSD operating systems offer a pspp package.
The project no longer maintains an official Windows build.
Data Model
Syntax
Commands
Programming