The following filters control your view of the dataset:
Examples of these filters can be seen in the following screenshot:
There is also a Keep Only/Exclude switch (shown at 5 above) that allows you to simplify your view of the current dataset.
There is a help window available when you hover over the information button in the top left hand corner of each report. It provides a summary of the names of the switches and definitions that are relevant to the particular report. Refer to the Data Quality Dashboard for an example.