Applying Disruptive Preference Test Protocols to Increase the Number of "No Preference" Responses in the Placebo...

One form of paired preference test protocol requires consumers to assess 2 pairs of products. One is the target pair under consideration, while the other is a putatively identical pair named the "placebo pair" which is also presented as a control. Counterintuitively, the majority of consumers report preferences when presented with the placebo pair. Their response frequencies are hypothesized to be those of consumers having "no preference" and are compared with the response frequencies elicited by a target pair, to determine whether the target pair elicits significant preferences. The primary goal of this paper was to study the robustness of 2 new so called disruptive protocols that reduced the proportion of consumers, who reported preferences when assessing a putatively identical pair of products. For this task, the tests were performed in a different language, in a different country, using different products from before. The results showed that the proportion of consumers reporting preferences for the placebo pair was reduced, confirming earlier work. Also, comparison of d' values showed a lack of significant overall differences between the placebo and target pairs, while chi-squared analyses indicated significant differences in the response frequencies. This indicated that the sample was segmented into 2 balanced groups with opposing preferences.