Release Name: 0.5.1

Notes:
A suite for your basic and advanced statistics needs. Descriptive statistics, multiple regression, dominance analysis, scale's reliability analysis, bivariate statistics and others procedures.


Changes:
=== 0.5.1 / 2009-10-06

* New Class Bivariate::Tetrachoric, for calculation of tetrachoric correlations. See http://www.john-uebersax.com/stat/tetra.htm for information.
* New Dataset.merge
* New Vector.dichotomize
* New ItemReliability.item_difficulty_analysis
* New module Statsample::SPSS, to export information to SPSS. For now, only tetrachoric correlation matrix are provided
* All SpreadSheet based importers now accept repeated variable names and renames they on the fly
* MultipleRegression::BaseEngine moved to new file
* Bug fix for MultipleRegression::GslEngine checks for Alglib, not GSL