For instance, over 9m people are meant to have watched the X Factor last Sat. as opposed to 2m for DanceX. But how do they know this? Those 9m people don't have recording devices in their TV's! I've always wondered this.
2007-08-21 05:49:05 · 3 answers · asked by Sue B 2 in Science & Mathematics ➔ Mathematics
They do surveys and statistically estimate the number of people viewing each channel. See:
http://en.wikipedia.org/wiki/Nielsen_Ratings
The group that does television ratings is called the Nielsen company. They survey enough homes, in enough different places, to statistically presume that they have an accurate picture of what viewership was like for any given show.
2007-08-21 05:58:39 · answer #1 · answered by сhееsеr1 7 · 0⤊ 0⤋
There are a statistically derived sample size of people that have their views recorded. From this, the percentage viewing each show can be determined and then applied to the population with a standard error e.g. 15% +/- 2%
2007-08-21 12:58:39 · answer #2 · answered by gebobs 6 · 0⤊ 0⤋
About 10,000 homes have Nielsen meters (I forget the number). These homes are then weighed for demographics to estimate the total number of people who watched.
Their site has lots of info on what they do and how they do it.
2007-08-21 12:57:49 · answer #3 · answered by Baccheus 7 · 0⤊ 0⤋