VOI_Data.zipVolume of Interest: Exploring New Data Types in Urban Functional Zones

With the acceleration of global urbanization, it has become a challenge to realize the refined identification of urban functional zones. Traditional methods based on POI data are insufficient in identifying the functional characteristics of different regions. The limitations of the imprecision of basic unit settings, the ambiguity of POI reclassification standards, and the vagueness of functional zone definition in previous studies have become significant obstacles to obtaining accurate identification results. To address these issues, this study proposes a method for extending POI data to three-dimensional space and generating the VOI (Volume of Interest) data. Taking a small region in Hong Kong as an example, a series of indicators were employed to quantify functional characteristics and then compared the experimental results with those obtained from the POI-based method. The final identification overall accuracy and kappa coefficient reached 85.67% and 0.7619, respectively, indicating that the VOI-based method is largely consistent with the actual situation. The analysis showed that VOI data contains richer and more comprehensive urban spatial information, which can better reflect the connections and influences among different regions within cities. This study can provide a reference case for the in-depth research of urban functional zones.