Reducing Choice Set Sizes for Factorial Plans

• Activity Number: 683
• Type: Contributed
• Date/Time: Thursday, August 5, 2010 : 10:30 AM to 12:20 PM
• Sponsor: Section on Statistics and Marketing
• Author(s): Pallavi Chitturi*+ and Jing Chen
• Companies: Temple University and Temple University
• Keywords: choice experiments ; factorial plans ; choice sets ; profiles ; attributes ; interactions

Abstract

In choice experiments the investigator organizes profiles into systematically constructed choice sets, where the profiles are designed on the basis of all attributes. When the number of attributes or attribute levels becomes large, the profiles in a single choice set may be too numerous for respondents to make precise decisions. In this paper we present strategies for reducing the number of profiles and the sizes of choice sets. We discuss strategies such as sub-setting choice sets, sub-setting levels, and sub-setting attributes. Designs where two-way and higher order interactions are estimated are particularly prone to requiring many profiles. The number of profiles may be reduced if it is only required that a subset of interactions be estimable. We provide designs in which only a subset of two-way and three-way interactions are estimated for factorial experiments.