Release Name: 0.6.6

Notes:
A suite for basic and advanced statistics on Ruby. Tested on Ruby 1.8.7, Ruby 1.9 and JRuby 1.4 (Ruby 1.8.7 compatible) 

Includes:
* Descriptive statistics: frequencies, median, mean, standard error, skew, kurtosis (and many others).
* Imports and exports datasets from and to Excel, CSV and plain text files.
* Correlations: Pearson's r, Spearman's rank correlation (rho), Tetrachoric, Polychoric
* Regression: Simple, Multiple, Probit  and Logit
* Factorial Analysis: Extraction (PCA and Principal Axis) and Rotation (Varimax and relatives)
* Dominance Analysis, with multivariate dependent and bootstrap (Azen & Budescu)
* Sample calculation related formulas


Changes:
=== 0.6.6 / 2010-03-22
* Set ReportBuilder dependency to '0.2.~' version, because future API break
* Removed Alglib dependency
* Factor::PrincipalAxis and Factor::PCA reworked
* Standarization of documentation on almost every file
* New Statsample::Test::Levene, to test equality of variances
* Constant HAS_GSL replaced by Statsample.has_gsl?
* PCA and Principal Axis test based on R and SPSS results
* Bug fix on test_dataset.rb / test_saveload
* Added Rakefile
* Demos for levene, Principal Axis