Clustering can also be performed: by the internal audit When the auditor uses the 'matching information in key data fields' process, the expectation is that: there should always be variances there should only be variances when two different databases are used there should be minimal variances there should be no matches before the data is transferred to the external auditors by graphing data in a way that allows for a simple regression analysis by graphing data in a way that allows for visual identification of groups by the client's legal counsel, if necessary