Core Weka

• GUIChooser now has a plugin exension point that allows implementations of GUIChooser.GUIChooserMenuPlugin to appear as entries in either the Tools or Visualization menus
• SubsetByExpression filter now has support for regexp matching
• weka.classifiers.IterativeClassifierOptimizer - a classifier that can efficiently optimize the number of iterations for a base classifier that implements IterativeClassifier
• Speedup for LogitBoost in the two class case
• weka.filters.supervised.instance.ClassBalancer - a simple filter to balance the weight of classes
• New class hierarchy for stopwords algorithms. Includes new methods to read custom stopwords from a file and apply multiple stopwords algorithms
• Ability to turn off capabilities checking in Weka algorithms. Improves runtime for ensemble methods that create a lot of simple base classifiers
• Memory savings in weka.core.Attribute
• Improvements in runtime for SimpleKMeans and EM
• weka.estimators.UnivariateMixtureEstimator - new mixture estimator

In packages

• New discriminantAnalysis package. Provides an implementation of Fisher's linear discriminant analysis
• Quartile estimators, correlation matrix heat map and k-means++ clustering in distributed Weka
• Support for default settings for GridSearch via a properties file
• Improvements in scripting with addition of the offical Groovy console (kfGroovy package) from the Groovy project and TigerJython (new tigerjython package) as the Jython console via the GUIChooser
• Support for the latest version of MLR in the RPlugin package
• EAR4 package contributed by Vahid Jalali
• StudentFilters package contributed by Chris Gearhart
• graphgram package contributed by Johannes Schneider