Experimentation in the 21st century: The importance of external validity

Much of the consumer behavior literature is devoted to what has been referred to as theory applications (TA) research in which the main focus is on laboratory experiments with student subjects and high internal validity. In this article, the author argues that external validity concerns should be given more attention, particularly in TA research. Three recommendations are made for implementing these concerns: (1) consumer behavior articles should be required to have a section indicating how increased levels of external validity can be obtained with other studies, (2) "joint ventures" between consumer behavior and marketing science researchers can be profitable and should be encouraged, and (3) analyses of electronic scanner panel data or other secondary data can be used to generate higher levels of external validity. Three examples are given from the marketing literature of how findings from experiments and scanner data can be combined to advance a stream of research.