The measurement of accessibility and connectivity in air transport networks

In the analysis of air transport networks, several interrelated concepts such as accessibility, connectivity, resilience, criticality, and vulnerability are commonly mentioned. Despite the plethora of empirical applications across many disciplines, there is no consistent set of definitions for them. Accessibility, defined by Hansen (1959) as “the potential of opportunities for interaction, " will be the nexus point in this chapter to provide a better understanding of all other concepts mentioned above. In this sense, traditional accessibility indicators will be adapted to air transport networks in relation to four dimensions: (1) land use; (2) the transportation system; (3) time periods; and (4) passenger segments. Using this categorization as a reference, this chapter will provide a consistent review of air transport accessibility indicators jointly with other related concepts such as connectivity, criticality, resilience, and vulnerability as all of them play an important role on aviation competition under the perspective of different stakeholders such as policy makers, airports, airlines, and passengers.