When creating a dashboard, you may want to set a hard filter on a measure or attribute across a whole dashboard. To do this you can use the Scope Widget. Below are the steps to create and apply a Scope Widget to a Dashboard, using in this specific example the OnTime Dataset Salesforce has used as part of the Salesforce Analytics Brownbelt.
Step 1 - Choose Count of Rows on a dataset of your choosing and select the filter button on a lens. I am using the OnTime Dataset.
Step 2 - Choose Arrival delay by clicking on the arrow on the right and enter the figures from: 10 and To: 30. This has filtered in this dataset "OnTime" flights where the arrival delay is between 10 - 30 minutes.
Step 3 - Apply the Filter to the dataset, and take a Snapshot of this lens adding the lens to a dashboard or creating a new dashboard.
Step 4 - Choose the Scope Widget and select the filtered step from the left handside to add the step to the Scope Widget.
Step 5 - Once the step has been added to the Scope Widget, you will see that the filtered field and the specific filter applied to the Scope Widget and Dashboard. In this case there is now a Global filter of flights with an arrival delay between 10 - 30 Minutes on the "OnTime" dataset.