In a traditional importance-performance analysis (IPA), the information of uncertainty for importance and performance does not normally take into account from the survey but does commonly exist in practice. To further consider the uncertainty for each item from the survey results, the IPA under uncertainty method is proposed in this study. The traditional IPA possesses the ease of calculation and can be further viewed as a special case of the proposed IPA under uncertainty method, which is more complicated for computation but provides much more information for a decision maker to judge the strengths and weaknesses effectively by considering sampling, instrument effects, measurement conditions, sample effects, computational effects, random effects, etc. Finally, a brief case is illustrated to show how the proposed IPA under uncertainty method works and what the differences are between the traditional IPA and proposed methods.
