Nielsen collects national TV ratings by using a "people meter." This is a box that is attached to televisions, DVRs, cable boxes, and satellite dishes in about 30,000 households across the country; has a remote control that is used to indicate when a viewer begins and finishes watching a TV program; and stores and then transmits the viewing information to Nielsen each night. The information Nielsen is collecting is referred to as
-sensitivity data.
-interactive industry data.
-internal secondary data.
-observational data.
-external secondary data.
Answer: observational data.