From Commuters to Explorers: Modal Inertia, Behavioral Commitment, and the Segmentation Logic of Flat-Rate Urban Mobility

Abstract

Urban residents do not fail to explore their cities because transit infrastructure is absent — they fail because behavioral habituation compresses their effective activity spaces far below objective accessibility boundaries. We term this condition modal inertia. This paper reports on a three-week social experiment in which 559 residents of a high-density metropolitan residential district in western Tokyo received unlimited access to a Digital Mobility Pass integrating a dedicated light rail line, four bus routes, and an electric micro-mobility sharing service for 2,000 JPY. Drawing on post-experiment survey data from 237 respondents (42.4% response rate) and 6,983 digital ticketing activation logs, we identify a four-segment behavioral typology and demonstrate that the number of transport modes actively combined, not demographic variables, is the primary predictor of behavioral change. Tri-modal users reported daily spending increases at 47.8%, against 33.3% for single-mode rail/bus users — a 43.5% relative differential sustained across both daily and leisure consumption contexts. The design implication is precise: MaaS interventions should be engineered to dissolve modal inertia, not merely to expand modal choice.

Keywords: MaaS, Modal Inertia, Behavioral Typology, Activity Space, Urban Exploration, Flat-Rate Mobility, Social Experiment

DOI: 10.54941/ahfe1008147