The aim of data mining as a scientific research is developing methods to analyze large amounts of data in order to discover interesting regularities or exceptions. Typical problems, which should be resolved during developing effective data mining algorithms, arise from the large sizes of both: The data sets used in the data mining process and the patterns results sets (for example in rules) which form discovered knowledge. Scientific researchers are oriented to find the most advantageous (i.e. most effective) solutions both during the data preparation stage and exploration and finally post- ...