statsample 0.18.0

A suite for basic and advanced statistics on Ruby. Tested on Ruby 1.8.7, 1.9.1, 1.9.2 (April, 2010) and JRuby 1.4 (Ruby 1.8.7 compatible). Include: * 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), point biserial, tau a, tau b and gamma. Tetrachoric and Polychoric correlation provides by +statsample-bivariate-extension+ gem. * Intra-class correlation * Anova: generic and vector-based One-way ANOVA and Two-way ANOVA * Tests: F, T, Levene, U-Mannwhitney. * Regression: Simple, Multiple (OLS), Probit and Logit * Factorial Analysis: Extraction (PCA and Principal Axis), Rotation (Varimax, Equimax, Quartimax) and Parallel Analysis and Velicer's MAP test, for estimation of number of factors. * Reliability analysis for simple scale and a DSL to easily analyze multiple scales using factor analysis and correlations, if you want it. * Dominance Analysis, with multivariate dependent and bootstrap (Azen & Budescu) * Sample calculation related formulas * Structural Equation Modeling (SEM), using R libraries +sem+ and +OpenMx+ * Creates reports on text, html and rtf, using ReportBuilder gem * Graphics: Histogram, Boxplot and Scatterplot