Split-Sample Tests of ‘‘No Opinion’’ Responses in an Attribute-Based Choice Model

Researchers using questionnaires to elicit preferences must decide whether to include response options that allow respondents to express ‘‘no opinion.’’ Using a split-sample design, we explore the implications of alternative answer formats including and not including no-opinion responses in an attribute-based choice experiment. The results indicate that using multiple no-opinion responses may enable researchers to differentiate between respondents who choose no-opinion options due to satisficing and those expressing utility indifference. Existing literature suggesting no-opinion responses may be treated as ‘‘no,’’ but our results show treating no-opinion responses as no yields substantially disparate preference estimates. (JEL