Normally there is a small sample of people that have special boxes that record what they watch and when, and the data is uploaded. Based on this they extrapolate the data for the whole country. The bigger the sample size, the more accurate the results.
Before some conspiracy nut job jumps in, no they cannot automatically determine what you watch on TV. Its a one way system. (Streaming on the other hand is completely different)
INTRODUCTION
AGB Nielsen has measured television in South Africa using peoplemeter technology since 1989. The research is funded via a 1% levy on all measured advertising and is managed by the joint industry committee, the South African Advertising Research Foundation (SAARF).
Since 1989, the panel size has gradually increased from approximately 400 households to the current 1356 households.
The major client is SAARF who pays for the main panel of 1200 households. Oracle Airtime Sales, the sales house of the satellite and Pay TV broadcaster, also contributes by paying for an additional 156 satellite households, which provides substantial over-sampling of satellite households and consequently more robust data.
Satellite households are measured via software on the decoder, which outputs the channel viewed to the meter. Although South Africa was one of the first countries to do this, the system has proved reliable and robust.
Since inception, the television audience measurement (TAM) service has provided daily ratings of all program, commercial breaks and individual spot data. The data has always been issued on a weekly basis (4 days after the week in question), although a limited overnight service providing ¼ hour data is now available.
Negotiations with SAARF to deliver a full overnight service in the future are being finalised. It is planned that the overnight service will include commercial breaks and individual spots as well as increase panel coverage to include rural areas. Forced rotation of older panel households will also be introduced.
Plans are also in place to measure interactive usage in satellite households which is enabled via our proprietary software installed on the decoder boxes.
At Nielsen, we believe innovation is the key to success and we understand what consumers watch and buy.
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