PSPP is a free version of SPSS, a proprietary program. It performs statistical analysis of sampled data. It is multi-platform and comes with GUI and command line interfaces.
License: GNU General Public License v3
Changes:
This release has a graphical interface that allows you to enter data and variable definitions interactively. Commands may be executed in syntax form, or by using the interactive dialog boxes. REGRESSION is a new procedure for fitting linear models to data. NPAR TESTS is a new procedure for non-parametric tests. It supports binomial and chi-square tests. RANK is a new procedure to rank variables. It supports numerous forms of ranking. FREQUENCIES can now output histograms and pie charts.
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