Occasionally an existing rule needs to be retrained.  This sometimes happens when a rule is not detecting all the duplicates or a large amount of new data has been added to Salesforce. 


Notice that an existing rule has a version number.  To re-train this rule, select it from the list and press OPEN.  


Then select the TRAIN button and CONFIRM to create a new version.


On the next screen, you are asked to evaluate if a pair of records is a duplicate.  You can answer, Yes, No or Not Sure.   The process is the same as training a new model, except the training picks up where the previous version stopped.  

Press the Finish button to complete the re-training.  Note that the a new version of the rule will be created.

Good to know:  All the versions of a rule are available for selection by a dataset