Appling GM(0,N) in the user´s cognition of design research - An example in smart phone holster

The purpose of the study is to investigate the preference cognition of smartphone leather cases in Taiwan, and provide reference for further product design, and then promote the marketing function. In the analyzing process, we ignore the occupation of the examinees; instead, we classify the examinees into three groups according to their age and gender. The three groups are mature, middle-aged and youth. We propose the representative samples and analyze their preference based on the shape, structure, color, texture, materials, convenience, usability, quality, value, and the protective effect. The study aims to understand the preferences of smartphone leather case in different groups, and provide correct reference for further design. First, apply GM (h, N) model to analyze the weighting of influencing factors and their order structure. Second, analyze the influencing factors among the three groups. Then, the results can become a systematic application reference model to solve the uncertain issues of new product design and to provide the values of future product design application.