Data driven functional regions

National scale changes in social, economic, and demographic variables are the result of a diverse range of interactions at the local, regional, national, and international level. Even within a single local area, there are a myriad of factors driving change and promoting stability and/or instability (Green & Owen 1990). The past several decades have seen increasing recognition that the standard administrative areas used by governments for policy making, resource allocation, and research do not provide meaningful information on actual conditions of a particular place or region (Ball 1980, Casado-Dı́az 2000). As such, there has been a move towards the identification and delineation of functional regions, commonly based on the conditions of local labour markets (Smart 1974, Casado-Dı́az 2000, Coombes 2002, Watts 2004). Ball (1980) suggests that the use of a spatial definition of local labour market conditions, such as functional regions, is of particular relevance for several reasons, including as a means of presenting information and statistics on employment and socio-economic structures, as well as assessing the effectiveness of regional policy decisions, and local government reorganisation. Journey to work behaviour is widely cited as one of the most appropriate indicators of local labour market dimensions (e.g., Ball 1980, Gerard 1958, Vance 1960, Hunter 1969), and as a result, is often used to develop functional regions. As such, a functional region is often defined as a geographical region in which a large majority of the local population seeks employment, and the majority of local employers recruit their labour (Ball 1980, Coombes & Openshaw 1982, Casado-Dı́az 2000). Functional regions are generally