Different perspectives are indispensable for public space quality: Exploring the relationship between urban design quality and physical disorder

Public space quality is a multidimensional concept. Urban design quality and physical disorder represent it from the perspectives of design and maintenance, respectively. However, the practical relationship between these two factors remains unclear, raising questions about the necessity of measuring multiple dimensions of public space quality simultaneously. Based on classical studies and theories, this study developed index systems for both factors. Utilizing artificial virtual auditing and deep learning models, including FCN and SegNet, the street visual quality of two Chinese cities was assessed from the perspectives of urban design and physical disorder using extensive street view images. The correlation between these two factors was explored. The results showed that the Spearman correlation coefficients for urban design quality and physical disorder were 0.308 and −0.085 in the two cities, respectively, indicating weak or unclear correlations. Additionally, the fit and explanatory power of the linear and nonlinear regression models constructed were poor, further demonstrating that it is difficult to predict and explain one variable using the other. In the robustness test, the results were further validated by including control variables related to urban vitality, cultural characteristics, and urban development, considering the impact of the distribution of the street view images, drilling down to more granular dimensions and extending the scope of the study to a wider area. The levels of design and maintenance of streets cannot be conflated or substituted, and neither can independently represent the overall space quality alone. Both are indispensable, making it crucial to separately assess and address space quality issues from different perspectives. These results broaden our understanding of high-visual-quality street space and provide references for urban planners and stakeholders in improving street space quality.