Road Damage Externalities and Road User Charges
提出一种新发现的道路损坏外部性，即车辆对后续车辆造成的运营成本远高于道路维护成本，并证明在稳态下平均道路损坏外部性为零，从而道路使用者收费只需覆盖交通引起的损坏部分。
subsequent vehicles, and these operating costs may be an order of magnitude larger than the road maintenance costs. The paper develops a theory to handle this newly identified extemality and establishes a remarkable result. If roads are repaired when they reach a predetermined critical condition (not necessarily optimally set) and if road damage is fully attributable to traffic, then in steady state with zero traffic growth the average road damage externality is zero, and the average marginal social cost of road use is equal to the average road maintenance cost. The result holds for arbitrary road damage and vehicle damage functions. Recent empirical studies reveal that weather accounts for a significant fraction of road deterioration, and in this case the road damage externality is no longer exactly zero, but is quantitatively negligible. The appropriate road user charge now only recovers the fraction of damage attributable to traffic.