Radio ratings are therefore the oldest form of telecommunication ratings. To understand radio ratings, you must be familiar with the following terms and concepts.
All telecommunication ratings are estimates of audience participation.
These estimates are based on audience surveys. The limited number of people sampled in ratings surveys accurately represents the larger total audience only if the survey methods are statistically valid. This means they must comply with the mathematic rules of random statistical sampling. Radio ratings measure the number of individual persons in the audience for each radio station. Since the 1950s, radio has become largely a local medium.