石川 城太

ABSTRACT This paper studies how carbon pricing affects greenhouse gas (GHG) emissions from international transport, production, and consumption of traded goods by modeling the international transport sector explicitly. Strategic behavior of a transport firm generates a novel mechanism of carbon leakage across borders and sectors. The effectiveness of carbon pricing depends on whether the backhaul problem (i.e., the imbalance of shipping volume in outgoing and incoming routes) is present. If the backhaul problem is absent, carbon pricing is effective in reducing global GHG emissions. With the backhaul problem, carbon pricing on goods production results in cross‐border carbon leakage. However, strategic freight‐rate setting by the transport firm mitigates this leakage. The opportunity for foreign direct investment (FDI) also affects carbon‐pricing effectiveness because the transport firm tries to deter FDI. Surprisingly, carbon pricing in the transport sector may not affect GHG emissions at all. Moreover, domestic carbon pricing on goods production may decrease GHG emissions from both transport and foreign production even if there is no domestic production under FDI.

This paper incorporates key stylized facts about the transport sector into the conventional international oligopoly model and explores how protectionist policies perform differently when transport costs are endogenous and subject to the backhaul problem (i.e., the imbalance of shipping volume in outgoing and incoming routes). A country’s protectionist policies, which benefit domestic firms and harm foreign firms in the conventional model, can harm domestic firms and benefit foreign firms if carriers avoid the backhaul problem. Protectionist policies may also lead to a facilitating practice. In the absence of the backhaul problem, both domestic and foreign consumers lose from protectionist policies.

As a result of global warming, carbon taxes and emissions trading policies are in the spotlight. However, lack of cross-country coordination can cause carbon leakage and increases in emissions. This column analyses the effectiveness of carbon taxes and border tax adjustment policies in reducing emissions and shaping firms’ decisions on abatement investment and firm location. It shows that a higher carbon tax can sometimes lead to higher global emissions and discourage investment in clean technology. Likewise, border tax adjustments should be designed carefully to ensure lower emissions and compatibility with WTO rules.

It is well known that multinational enterprises take advantage of corporate tax systems worldwide to avoid taxation. Transfer pricing is one common method used for profit-shifting, as intra-firm transactions are shielded from the market mechanism. Numerous guidelines and regulations have been implemented to tackle such profit-shifting, but challenges remain. This column theoretically explores how one such regulation, the ‘arm’s length principle’, affects the licensing strategies of multinationals in the presence of a tax haven. It shows that the mere existence of this principle may lead to further profit-shifting and may worsen the welfare of high-tax countries.

To address the issue of tax avoidance by multinational enterprises, governments impose transfer-pricing rules to control transfer-price manipulation. Using a theoretical framework allowing for the possibility of profit shifting, this column explores the interplay between transfer-pricing regulations and tax competition. It finds that the nature of tax competition can depend on the tightness of transfer-pricing regulation, and a tax-haven country does not always prefer lax transfer-pricing regulation. Thus, the incentives of the host and FDI source country can be aligned to set up global regulatory standards for transfer pricing.

We examine how trade liberalization affects South’s incentive to protect intellectual property rights (IPR) in a North–South duopoly model where a low‐cost North firm competes with a high‐cost South firm in the South market. The North firm serves the South market through either exports or foreign direct investment (FDI). The extent of effective cost difference between North and South depends on South’s imitation, which in turn depends on South’s IPR protection and absorptive capacity and North firm’s location choice, all of which are endogenously determined in our model. For a given level of IPR protection, South’s absorptive capacity under exports may be greater than under FDI. Even though innovation is exogenous to the model (and hence unaffected by South’s IPR policy), strengthening IPR protection in South can improve its welfare. The relationship between trade costs and the degree of IPR protection that maximizes South welfare is non‐monotone. In particular, South has an incentive to protect IPR only when trade costs are moderate. When masking technology or licensing is incorporated into the model, however, some protection of IPR may be optimal for South eve

For models of international trade to accurately represent the real-world costs, transport costs cannot be ignored. This column argues that, additionally, we cannot assume that transport costs are symmetrical, because of a backhaul capacity problem that constrains international shipping. Domestic tariffs, which benefit the domestic import sector and harm the foreign export sector in standard models of international trade, can also harm the domestic export sector and benefit the foreign import sector.

Using the footloose capital model with two countries, this paper studies different impacts of emission taxes and quotas on firm location and global emissions under trade liberalization. If only one country (North) sets a target of emissions, firms may have incentive to relocate to the other country (South). That is, the pollution haven effect could arise. We show that a further decrease in trade costs, given an emission regulation in North, increases firm relocation and global emissions only if trade costs are relatively low. Moreover, compared with emission taxes, emission quotas moderate firm relocation, which results in less pollution haven and hence less global emissions.

We explore the effects of environmental and trade policies with negative consumption externalities when a domestic firm and a foreign rival produce imperfect substitutes and compete in the domestic market. Consumption of the foreign product generates more emissions than that of the domestic product. Emission taxes reduce emissions, harm the foreign firm, but may benefit the domestic firm. Tariffs could mitigate externalities more "effectively" than emission taxes. Consumption subsides provided to the domestic product may raise emissions and worsen domestic welfare. Stringent environmental policies may induce the foreign firm to produce an environmentally friendly good, though environmental damages may increase.