Filtering by user role
When editing a View, scroll to View Settings and click "Filter & Sort"
Click the "Add Condition" button
Then choose "Created By User Role" from the first dropdown
Choose the role you wish to display entries from
If you choose "Any Role of Current User", the currently logged-in user's roles will be used
You can also use "is not"!
You can choose to exclude entries created by users with certain roles by selecting the "is not" comparison from the filter dropdown.
To show all entries that were not created by site administrators, you could add this configuration: "Created By User Role" "is not" "Administrator", as shown below.