the results derive fromdata mining in stage 2 are further reviewed in regard to the causes and effects. It is to identify the service weaknesses and its causes. In this empirical case, rule 1 is selected as a target example for the review because rule 1 involves the most citizen complaint cases (94 cases, see Table 2) with the highest confidence level 100%. The 94 complaint cases are illustrated in the three aspects after one by one review the contents of complaint raised by citizen. They are inadequate city construction design, insufficient operation procedures and apathetic service
interface. The three aspects concurrently exist in the service system which results in the 94 citizen complaints cases being raised.
The aspects are discussed in details as follows