Max Diff Scaling
MaxDiff is a methodology developed by Jordan Louviere et al., that results in interval scale measurements that are based on comparative judgments that can be easily performed, even when the number of attributes is not small. The task presents respondents with a set of items, usually 3 to 6, and simply asks them to select the most preferred and the least preferred in the set (or the most important, least important; best item, worst item, etc. In fact the method is also referred to as Best/Worst scaling). Respondents can typically handle a number of these evaluations, and may be asked to respond to 15, 20, or more sets.