An extensive empirical comparison of ensemble learning methods for binary classification

We present an extensive empirical comparison between nineteen prototypical supervised ensemble learning algorithms, including Boosting, Bagging, Random Forests, Rotation Forests, Arc-X4, Class-Switching and their variants, as well as more recent techniques like Random Patches. These algorithms were compared against each other in terms of threshold, ranking/ordering and probability metrics over nineteen UCI benchmark data sets with binary labels. We also examine the influence of two base learners, CART and Extremely Randomized Trees, on the bias–variance decomposition and the effect of calibrating the models via Isotonic Regression on each performance metric. The selected data sets were already used in various empirical studies and cover different application domains. The source code and the detailed results of our study are publicly available.     

Unsupervised feature selection with ensemble learning

Machine Learning - In this paper, we show that the way internal estimates are used to measure variable importance in Random Forests are also applicable to feature selection in unsupervised...     

Different Aspects of Clustering The Self-Organizing Maps

Self-organizing map (SOM) is an artificial neural network tool that is trained using unsupervised learning to produce a low dimensional representation of the input space, called a map. This map is generally the object of a clustering analysis step which aims to partition the referents vectors (map neurons) into compact and well-separated groups. In this paper, we consider the problem of the clustering SOM using different aspects: partitioning, hierarchical and graph coloring based techniques. Unlike the traditional clustering SOM techniques, which use k-means or hierarchical clustering, the graph-based approaches have the advantage of providing a partitioning of the SOM by simultaneously using dissimilarities and neighborhood relations provided by the map. We present the experimental results of several comparisons between these different ways of clustering.