Exploring point zero: a study of 20 Chinese cities

Abstract

ABSTRACT A point zero represents a central geographical location of a city, which is essential for not only measuring distances, but also understanding the historical and/or cultural origin of a city. Although extensive studies have focused on delineating city centers, to our knowledge, no studies have paid attention to determining the location for a point zero. Here, our goal is to investigate various potential approaches for identifying such a location. Specifically, three typical approaches, geometric-based, topological-based, and thematic-based, are proposed to recommend point zeros and different scales, administrative divisions, kernel density surfaces, and regions enclosed by ring roads are used for analysis. The effectiveness of different approaches and scales are evaluated and compared by calculating an offset distance between recommended and actual point zero locations in 20 Chinese cities. Using the different approaches, the average offset distance for most Chinese cities is 2–4 km, and the thematic-based approach performs best. Both the topological-based and thematic-based approaches are less sensitive to the analyzed scale than the geometric-based approach. The results indicate that it is possible to determine the approximate location for a point zero from geographical data. Based on the buffer zone of such a location, an actual point zero may further be recommended.