Lastly, it brings me back to conventional ratings such as diary and the PPM. For the PPM, is a subscription service such as SiriusXM encoded so that they get ratings credit? Likewise, if a diary listener mentions listening to another platform, does that other service get credit? It would seem a SiriusXM would have to ensure the vast majority of their channels are attracting new subscriptions while keeping attrition as low as possible. But how do they do it?
While the long-range goal of PPM measurement is to encompass all electronic media, such as radio, TV, cable, streaming and related services, at present it measures encoded terrestrial radio (AM, FM, HD channels and their streams) only. The system originally was designed and intended to be tested for radio and TV together, but in about 2003 Nielsen dropped out, leaving Arbitron to finish the development alone.
The PPM began conceptually around 1990, well before satellite and Internet streaming. By 1995, they had a working prototype, but the PPM device, now the size of a pager, was the size of an average brick... and about as heavy. But the point here is that the concept is now is nearly 30 years old.
Sirius / XM could encode all the channels, and subscribe to the PPM service, but the results would only cover 48 US markets. And the real issue is that ad sales are likely not large enough to warrant the expense. For audience preferences, they apparently do surveys of subscribers to determine channel usage. Also, satellite knows that, other than Stern and certain sports features, subscribers like satellite because of the accessibility of a variety of formats with no ads. So knowing just channel rank is not a key issue; what is important is whether the service satisfies a variety of needs at different times for each subscriber, and that is a matter for perceptual research.