Analysing trends of quality pata by means of new pre processing methods

This paper presents pre-processing methods to analyse interdependent system data that varies with time due to "external impacts". These "external impacts" can be self-made by management changes or can result from occurrences that have no connection to the system but still influence it. Using this method, the quality management can be enabled to reveal which external impacts worsened or improved the performance of the given system, can control the system flow and management course and - if needed - correct it before a lot of damage is done.