Addressing quality issues of historical GIS data: an example of Republican Beijing

Abstract

This article addresses several issues related to historical GIS data using a project studying the social culture of Republican Beijing as an illustration. For large-scale historical GIS projects, certain data layers or themes are fundamental to and provide the context for various types of investigation. We suggested that these data may be regarded as framework data, similar to the concept of the core dataset identified in the US National Spatial Data Infrastructure (NSDI) framework, but in a GIS project context. Due to various reasons, most historical GIS data always invite concerns about their quality. We discussed how typical spatial data quality concepts are partially applicable to historical GIS data. We also highlighted the data quality aspects that are more significant to historical than contemporary GIS data. Compiling high-quality historical GIS data is challenging. We used the data layer of temple locations as an example to illustrate the process of using a set of principles to resolve the inconsistencies of data from multiple sources to deal with location accuracy and data completeness problems. Two common but related quality concerns of historical GIS data are their relatively low spatial resolution and imprecise locations. The original population dataset of Republican Beijing suffers from these two issues. Using ancillary data, more precise population locations and population distribution at a higher resolution were estimated. Compilation of historical GIS data requires fusing data of different sources in order to enhance the quality of the data.