Extraction of Customer’s Latent Viewpoints by Mutual Evaluation

To respond to increasingly diversifying customer's needs of a product, it has become important to acquire potential viewpoints of the customer’s criteria for product evaluation in the design process. Furthermore, emotional needs, such as design styling and user-friendliness, have become increasingly important for a differentiation strategy in a market in which products have similar performances and functionalities. To acquire the customer’s emotional need and its cognitive structure, a laddering-based interview is often conducted. Frequently appearing patterns among the acquired answers are considered to be representative of the customer’s viewpoints. However, the truly effective viewpoints of the customers are often hidden in their subconscious. The majority answers may represent viewpoints of which most subjects are consciously aware but which are not so effective in suggesting innovative designs. On the other hand, the minority opinions may include potential and important viewpoints. In this paper, we demonstrate this experimentally using the case study of a plastic-bottle design. To extract such potential viewpoints, we conduct a mutual evaluation experiment in which the subjects evaluate their own and other subjects’ viewpoints extracted with a laddering-based interview. The results showed that commonly unexpected viewpoints, of which most subjects are unaware, included more effective viewpoints than the commonly expected ones, which frequently appeared among the subject’s viewpoints in the interview. Thus, the truly important viewpoints of a customer’s criteria for product evaluation are hidden in the subconscious, and not easily extracted by only interviews. The mutual evaluation among subjects helps to extract such latent viewpoints.