“…, m. Another limitation is its expensiveness, as the acceptance of the compatibility hypothesis requires a test (with positive result) on each cycle within the graph (T • , E, R). Algorithms may be devised to simplify this testing process by exploiting redundancies implicit in the graph (Wang and Kuo, 2010;Kuo and Wang, 2011;Yao, Chen and Wang, 2014). Lastly we remark that, of the cases covered by Theorem 3, special notice should be given to the case in which the conditioned variables Y 1 , .…”