The Impact of Choice Inconsistencies in Stated Choice Studies

A new test procedure revealing mutuallyinconsistent choices has been developed andapplied to Stated Choice data. Our analysisshows that inconsistent choices commonly occurin several Stated Choice tasks. An applicationof the test to the Norwegian Value of Timestudy data shows that failing to excludeinconsistent choices resulted in asubstantially higher Value of time. Theinconsistent choices were made by less educatedparticipants. As the tasks were undertaken inthe easy context of choosing travelalternatives with three attributes,practitioners of more complex and cognitivedemanding designs should be particularilyconcerned with these results.