i hear a lot about 3.5 million viewers watching doctor who or what not, but how do the stations know that there are some millions watching a single program? how are the figures generated?
There is a group of people who have chips on their TV or sky box or whatever and they send a signal to a company the company then counts up how many out of these people watch dr who then get an average. They then use this against the amount of people who have tv's and this gives them a rough estimate.
