The SAP reference model contains more than 600 non-trivial process models expressed in terms of Event-driven Process Chains (EPCs). We have automatically translated these EPCs into YAWL models and analyzed these models usingWofYAWL, a veri¯cation tool based on Petri nets. We discovered that at least 34 of these EPCs contain errors (i.e., at least 5.6% is °awed). We analyzed which parts of the SAP reference model contain most errors. Moreover, based on 15 characteristics (e.g., the size of the model), we used logistic regression to ¯nd possible pre- dictors for these errors. This systematic analysis of the SAP reference model illustrates the need for veri¯cation tools such as WofYAWL
