Quantifying the Similarity of Urban Forms through the Building Morphology Complexity Index

Xiaochen Fan, Rui Chen, Yuming Lin

Abstract: Urban forms exhibit significant diversity across different cities in structure and layout, embodying semantic geographical, historical and cultural distinctions. Thereby, quantifying the similarity of urban forms among cities worldwide would provide insights into patterns and legacies that are deeply conserved inside their characteristics. Although conventional studies have explored various methods to identify unique features of urban forms, there still lacks a comprehensive methodology to quantify their similarities systematically. In this study, we exploit buildings and their footprints, the fundamental physical structure in urban space, as the data source for urban form quantification. Specifically, we apply the building morphology complexity index to over 8.66 million buildings, characterizing the morphological similarities among 47 cities across the globe. Notably, the results validate that building morphology complexity is capable of measuring the spatial characteristics of urban forms and scaling to quantify intercity similarities. To further provide a semantic analysis, we cluster the representative types of urban forms and calculate spanning values of building complexities by using statistical and quantitative measures.