The user list generation server can then add the selected users to the user list in 410. The user list in 410 can be the final user list 138 (e.g., the user action group) described in reference to FIG. 1. The user list can now include one or more users from the original list, one or more of the additional users in the same group as at least one of the users from the original list (e.g., users that are part of the same user interest group as at least one of the users from the original list), and the proper subset of users from the intermediate list that were selected based on one or more signals described above. The user list, therefore, has been expanded to include more users who share common interests and perform similar actions. Not only has the user list been expanded, but it has also been refined and/or post-processed to more accurately identify users who share common interests and who should receive similar or same digital components. Using the techniques described herein, the user list can identify users without relying on the users' private or personal information. A larger and homogenous user list can further preserve the privacy of each user in the user list.
Example Processes for Determining User Scores for Adding the Users to User Lists
