Glossary
Ratings & Audience
Portable People Meter (PPM)
A device-based ratings method that passively detects which stations a panelist is exposed to.
The Portable People Meter is a pager-sized device carried by ratings panelists that automatically detects inaudible codes embedded in station audio, logging exposure without the person recording anything. It replaced paper diaries in larger markets.
Because PPM measures actual exposure minute by minute, it rewards stations that hold attention continuously — which raises the stakes on tune-out moments like weak breaks or long stop sets.