Pattern Recognition Approaches to Solving Combinatorial Problems in Free   Groups
  We review some basic methodologies from pattern recognition that can be applied to helping solve combinatorial problems in free group theory. We illustrate how this works with recognizing Whitehead minimal words in free groups of rank 2. The methodologies reviewed include how to form feature vectors, principal components, distance classifers, linear classifiers, regression classifiers, Fisher linear discriminant, support vector machines, quantizing, classification trees, and clustering techniques. 
Robert M. Haralick, Alexei D. Miasnikov and Alexei G. Myasnikov