We study optimal pollution abatement under a mixed oligopoly game when firms engage in emissions-reducing R&D that is … certain conditions, the optimal pollution tax is positive; otherwise, the tax reverts to a subsidy. Comparing mixed and …

We study the optimal and equilibrium size of cities in a city system model with environmental pollution. Pollution is …, if pollution is local or per capita pollution increases with population, we find that equilibrium cities are too large …. When pollution is global and per capita pollution declines with city size, however, equilibrium cities may be too small …

baseline model by adding climate-induced fluctuations around the growth trend and stock-pollution effects, demonstrating …