Comparison with Standard Data
From Q1 2012, NRS has provided part of its readership data as probabilities for use in Reach & Frequency media planning programmes.
This is a technical change to the way in which the data are held, not in the way they are collected. Great care has been taken to ensure that the probabilities data are as close as possible to the original binary data. At the level of All Adults, the probabilities Average Issue Readership for individual titles matches the binary Average Issue Readership.
These changes were agreed by NRS and its Technical Committee, comprising members of the Survey’s stakeholders, the IPA, NPA and PPA.
The standard NRS currency remains in the standard binary format – this includes all published data, and data used in Crosstab programmes.
However, there may be differences between the two when looking at demographic sub-groups, and though these differences are mostly small, users should be aware of this. The probabilities data are only for the use of Reach & Frequency. If quoting average issue readership (AIR) data for individual titles, users should continue to use the standard binary data.
Why have we done this?
- The different bureaux (IMS, KMR, Telmar) have their different models for calculating Reach & Frequency
- Previously, the same shedule could generate different reach according to whether it was run by Nielsen IMS, KMR Choices or Telmar software and an agency and publisher looking at the same schedule could be seeing different results
- NRS providing its own probabilities for Reach & Frequency means consistency of results between the bureaux
- This allows users to carry out Reach & Frequency analyses in PADD as the website data are held as probabilities
- In the longer term, there will be greater integration of media research for multi-platform planning and holding the data as probabilities is a great advantage as probabilities are the more practical way of cross-analysing multi-media data, as in the IPA Touchpoints database
What this means in practice
- The standard NRS currency remains in the standard binary format – this includes all published reports and data used in Crosstab programmes
- If quoting Average Issue Readershp (AIR) data for individual titles, users should continue to use the standard (binary) data
- The probabilities data are ONLY for the use of Reach & Frequency in media planning
- In Telmar, the readership data held in the “MediaPlanner+ for PADD” menu are held as probabilities
- In Nielsen IMS, the readership data held in the “7news” section are held as probabilities
- In Kantar Choices, the readership data held in the “tbc” section are held as probabilities
In Summary
- To get Average Issue Readership (AIR) figures, use the Crosstab system
- Readership (AIR) figures provided in the quarterly NRS Notes and on the website will match what is seen in Crosstab
- The probabilities data are only for the use of Reach & Frequency
- The probabilities data match the standard (binary) data at the All Adults level
- However, if comparing probabilities data (in Reach & Frequency programmes) with standard Crosstab data there may be small differences for audiences other than All Adults
