[6月19日開催] The 177th「制度と組織の経済学」研究会 / Kentaro Nakajima (Institute of Innovation Research, Hitotsubashi University)

Presenter: Kentaro Nakajima (Institute of Innovation Research, Hitotsubashi University)
Title: “Economies of Density in Public Service Provision: Evidence from the Time Allocation of Waste Collection Trucks”

Date: Friday, 19 June 2026, 13:30–15:00

Venue: Zoom meeting
Registration: yuri-kitabayashi [at] iss.u-tokyo.ac.jp（東京大学中林研究室 北林様宛)

Abstract: How does urban density generate cost savings in spatially organized public services? This paper studies this question using one-second GPS records from municipal waste collection trucks in Japan. The data reveal the sequence of station visits and allow me to decompose truck operating time into service time at waste stations and non-service time associated primarily with spatial traversal between stations. I document three facts. First, active collection accounts for only about one-third of truck operating time. Second, station-level service exhibits economies of scale: service time increases with the population served by a station, but much less than proportionally. Third, higher population density is associated with substantially lower per-capita non-service time, making the traversal margin quantitatively central. As an interpretable benchmark, a one-percent increase in population density is associated with a cost reduction equivalent to an 11.13-percent reduction in waste generation per resident. Counterfactual exercises show that the fiscal consequences of population decline depend on both where residents are lost and how the station network adjusts. A uniform five-percent population decline raises aggregate per-capita operating cost by 0.83 percent when station density is fixed, but this increase is almost fully offset when station counts adjust with population. Population loss concentrated in high-density districts raises per-capita operating cost, whereas population loss concentrated in low-density districts reduces aggregate operating cost among the remaining population. These results highlight spatial concentration and service-network adjustment as important determinants of the fiscal sustainability of local public services in shrinking cities.

The Osaka Workshop on Economics of Institutions and Organizations　 https://sites.google.com/site/theoeio/Home

The meeting is organized in collaboration with International Public Policy Seminar