Assessing geographic data usability in analytical contexts by using sensitivity analyses of geospatial processes

The number and variety of sources of spatial data continues to expand, as do the debates regarding the quality and usability of such data, particularly those which are Free and Open Source (FOS) or free-to-use. The highest quality data is often expensive to obtain and the option of cost-free data sets is tempting for many users. With the existence of the huge hinterland of data quality research acknowledged, and a great number of studies investigating the usability of devices and interfaces, little attention has been paid to the usability of data, and even less into the usability of geographical data in typical GIS research situations. There has been some research into the use of volunteered geographic information (VGI) in the field of data quality theory and assessment (see for example Haklay, 2010; Zielstra and Zipf, 2010), but relatively few studies have incorporated sensitivity analysis involving the application of different sources of spatial data to a range of GIS tasks. Jones’s (2010) study into the use of open data in presenting and visualising public health information is one notable exception, with another being that of Higgs et al's (2012) examination of the impact of alternative approaches to measuring accessibility to green space. This study set out to address cross-cutting themes that are topical in GIS and geographical analysis given trends towards the use of open source data, namely: