PSPP can analyze sampled data, it is a program for statistical analysis of sampled data. It is a Free replacement for the proprietary program SPSS, and appears very similar to it with a few exceptions.
Its backend is designed to perform its analyses as fast as possible, regardless of the size of the input data. You can use PSPP with its graphical interface or the more traditional syntax commands.

The most important of these exceptions are, that there are no "time bombs"; your copy of PSPP will not "expire" or deliberately stop working in the future. Neither are there any artificial limits on the number of cases or variables which you can use. There are no additional packages to purchase in order to get "advanced" functions; all functionality that PSPP currently supports is in the core package.

PSPP can perform descriptive statistics, T-tests, linear regression and non-parametric tests. Its backend is designed to perform its analyses as fast as possible, regardless of the size of the input data. You can use PSPP with its graphical interface or the more traditional syntax commands.

PSPP Features:
1. Supports over 1 billion cases.
2. Supports over 1 billion variables.
3. Syntax and data files are compatible with SPSS.
4. Choice of terminal or graphical user interface.
5. Choice of text, postscript or html output formats.
6. Inter-operates with Gnumeric, OpenOffice.Org and other free software.
7. Easy data import from spreadsheets, text files and database sources.
8. Fast statistical procedures, even on very large data sets.
9. No license fees.
10. No expiration period.
11. No unethical "end user license agreements".
12. Fully indexed user manual.
13. Free Software; licensed under GPLv3 or later.
14. Cross platform; Runs on many different computers and many different operating systems.

The language accepted by PSPP is similar to those accepted by SPSS statistical products. The details of PSPP's language are given later in this manual.

PSPP produces output in two forms: tables and charts. Both of these can be written in several formats; currently, ASCII, PostScript, and HTML are supported. In the future, more drivers, such as PCL and X Window System drivers, may be developed. For now, Ghostscript, available from the Free Software Foundation, may be used to convert PostScript chart output to other formats.

PSPP is particularly aimed at statisticians, social scientists and students requiring fast convenient analysis of sampled data.

The license of this software is Free, you can free download and free use this office suite software.