12 th WCTR, July 11-15, 2010 – Lisbon, Portugal 1 LOCATION AND ACCESSIBILITY MEDIATED INFLUENCES ON OFFICE FIRM CLOSURE RATES: A PROPORTIONAL HAZARD MODEL Gustavo G. Manzato Faculty of Architecture, Building and Planning - Eindhoven University of Technology - P.O. Box 513 - 5600MB Eindhoven - The Netherlands - G.G.Manzato@tue.nl Theo A. Arentze Faculty of Architecture, Building and Planning - Eindhoven University of Technology - P.O. Box 513 - 5600MB Eindhoven - The Netherlands - T.A.Arentze@tue.nl Harry J. P. Timmermans Faculty of Architecture, Building and Planning - Eindhoven University of Technology - P.O. Box 513 - 5600MB Eindhoven - The Netherlands - H.J.P.Timmermans@tue.nl Dick Ettema Faculty of Geosciences - Utrecht University - PO Box 80115 - 3508TC Utrecht - The Netherlands - D.Ettema@geo.uu.nl ABSTRACT This paper comprises an exploratory study about the mediated influence of a set of location and accessibility attributes along with firm types on office firm closure. We use a proportional hazard modeling approach, examining the probability that an office firm will go out of business in any given year, conditional on it did not go out of business in the years before. Variables include urbanization levels and regional effects; accessibility to airports, train stations, shopping centers and the roadway network; availability of parking facilities and schools; demographic and economic aspects; effects of agglomeration economies; rent price; and the office firm economic activity type. Most of them presented significance on explaining firm closure. Also, interaction effects between covariates and firm types brought better understanding on firm closure patterns regarding urban characteristics. Assessing firm closure is part of a firm demographic approach to firm dynamics. In turn, this is part of a multi agent system to simulate the co-evolution of firm dynamics and changes in activity-travel patterns. Keywords: office firm closure, hazard models, firm dynamics, Cox regression