A color design evaluation methodology for the subway guidance system based on TFN-AHP and cloud model

Abstract In subway guidance systems, color serves as a key visual medium for information transmission, significantly influencing the travel experience. To quantitatively assess the color design of such systems, the study introduced an evaluation method based on the Triangular Fuzzy Number Analytic Hierarchy Process (TFN-AHP) combined with the cloud model. First, a color design evaluation index system for subway guidance was established, drawing on user interviews and literature review. The system was structured around three main aspects: Information expression, visual expression, and emotional connection. To manage the uncertainty inherent in the evaluation data, triangular fuzzy numbers were integrated with the AHP method to calculate the weights of the indices. Subsequently, the cloud model was introduced to generate digital features and comprehensive cloud maps, effectively reducing the ambiguity and randomness in the evaluation of color design in subway guidance systems. Finally, a comprehensive evaluation of the color design for the subway guidance system was performed. Three representative color design samples of subway guidance systems in China were studied using the proposed method, and the conclusions are as follows: (1) Color design in subway guidance systems should prioritize information orientation and effective communication. (2) The optimal sample showed relatively favourable behavior in central tendency, design performance, and evaluation stability. (3) The ranking remained relatively stable under variations in weight perturbations, supporting the robustness of the proposed method.