In the past years, recursive partitioning methods have gained popularity as a means of multivariate data exploration in various scientific fields, including, e.g., the analysis of microarray data, DNA sequencing and many other applications in genetics, epidemiology and medicine (cf., e.g., Gunther, Stone, Gerwien, Bento, and Heyes 2003; Lunetta, Hayward, Segal, and Eerdewegh 2004; Segal, Barbour, and Grant 2004; Bureau, Dupuis, Falls, Lunetta, Hayward, Keith, and Eerdewegh 2005; Huang, Pan, Grindle, Han, Chen, Park, Miller, and Hall 2005; Shih, Seligson, Belldegrun, Palotie, and Horvath 2005; Diaz-Uriarte and Alvarez de Andrés 2006; Qi, Bar-Joseph, and Klein-Seetharaman 2006; Ward, Pajevic, Dreyfuss, and Malley 2006).
