DStv PVR universe out of latest TAMSThe new TAMS universes, based on the July to December 2010 AMPS fieldwork period, will have a significant change to the TAMS panel when SAARF implements the AMPS 2010B universes on 1 August 2011. The DStv PVR universe will be removed from the TAMS universe until the PVR homes are incorporated into the panel sample. Historically, TAMS has attributed viewership behaviour based on standard decoder homes to represent the total DStv platform (including PVR homes). This was acceptable whilst the PVR incidence was low. This has grown rapidly over the past three years and is now an important component that should be measured separately. Its removal from the current universe is a necessary first step to take as SAARF moves to bring PVR and time-shift measurement into the TAMS panel within the next couple of months. The diagram below illustrates the current structure of the TAMS panel using the 2010A universes and the planned 2010B measurement structure. As PVR homes are mostly on the premium bouquet, their exclusion means the premium channels will show higher than average decreases. Summary of changes
SAARF recommends that August and September campaigns be relooked in light of these measurement changes. When using June/July 2011 as source data, planners must take into account that the impact of the exclusion of PVR homes affects channels differently. Therefore, different down-weight rules should be applied.
This is a broad rule of thumb, and there will be variation by target market. Finally, the industry should continue to plan DStv, using sound planning practices ie using break ratings and by ensuring their DStv sample sizes within TAMS are robust and stable. Ratings will still vary at spot-by-spot level, so overall campaign performance should be used to judge performance. |