“…The model has its origins in the shopping model initially developed by Huff (1963) and Lakshmanan and Hansen (1965) and shares many similarities to the gravity models widely used in location theory and urban planning (Isard, 1975;Senior, 1979). It was later formalised by Wilson and Wilson (1971), embedded into a dynamic Lotka-Volterra type system (Harris and Wilson, 1978) and has since been adapted to a range of applications in theory and practice, including trade (Fry, 2012), migration (Dennett and Wilson, 2013), higher education (Singleton et al, 2012), policing strategy (Baudains et al, 2013;Davies et al, 2013), analysis of archaeological sites (Davies et al, 2014) and distribution of city sizes (Favaro and Pumain, 2011).…”