adequate sample

In general: statistical term used to indicate that a test group is large enough to achieve satisfactory precision and thus minimize the element of chance as a factor affecting the data obtained.

Advertising: test group of people used in compiling audience data selected so that the group adequately represents the market to be tested. For example, if the desired market for a product is an upscale male audience 35 years old plus, these characteristics will be reflected in the sample.