Sensitivity to Hand Path Curvature during Reaching

People optimize reaching to make straight and smooth movements. We performed experiments characterizing human sensitivity to hand path deviations from a straight reach. Vision of the arm was blocked. Subjects either moved the hand along paths of constrained curvature, or a robot moved the relaxed limb along similar trajectories (active and passive conditions, respectively). Subjects responded after each trial whether or not they thought the movement curved convex right. In a series of three experiments, we tested the effects of modifying visual feedback of hand position to suppress curvature, isotonic muscle activation, and a distracter task on subjects ability to detect curvature during reaching. We found that both active reaching and artificial minimization of visual hand path deviations significantly decreased proprioceptive curvature sensitivity. Specifically, isotonic contraction of muscles antagonistic to the movement decreased sensitivity to curvature while agonistic contraction had no effect. The distracter task did not significantly affect proprioceptive sensitivity, though it did interfere with the detrimental effect of minimizing visual error feedback. These findings demonstrate that: 1) antagonist muscle activation decreases efficacy of proprioceptive feedback during hand path curvature estimation, and 2) vision\u27s dominance over proprioception can be manipulated by altering the attentional demands of the task

Domestic Policies, National Sovereignty and International Economic Institutions

To what extent must nations cede control over their economic and social policies if global efficiency is to be achieved in an interdependent world? This question is at the center of the debate over the future role of GATT (and its successor, the WTO) in the realm of labor and environmental standards. Current GATT rules reflect the primacy of market access concerns in GATT practice, and this orientation is seen increasingly as unfriendly to labor and environmental causes. Fundamental changes to GATT are being considered as a result, changes that would expand the scope of GATT negotiations to include labor and environmental policies, and would lead to a significant loss of sovereignty for national governments. In this paper we establish that there is no need for the WTO to expand the scope of its negotiations in this way. We show instead that the market access focus of current GATT rules is well-equipped to handle the problems associated with choices over labor and environmental standards, and that with relatively modest changes that grant governments more sovereignty, not less, these rules can in principle deliver globally efficient outcomes.

Can the Doha Round be a Development Round? Setting a Place at the Table

A fundamental objective of the Doha Round of WTO negotiations is to improve the trading prospects of developing countries. The 2001 declaration from the WTO Ministerial Conference in Doha, Qatar, commits the member governments to negotiations aimed at substantial improvements in market access with a view to phasing out export subsidies, while embracing “special and differential treatment” for developing countries as an integral part of all elements of the negotiations. The main message of this paper comes in three parts. First, these stated aims are incompatible from the perspective of our economic analysis; thus, if these aims are pursued as stated, then we conclude that they are unlikely to deliver the meaningful trade gains for developing countries that the WTO membership seeks. Second, in attempting to integrate its developing country membership into the world trading system, the WTO may face a “latecomers” problem that, while occurring also in earlier rounds, is unprecedented in its scale in the Doha Round, and which could potentially account for the current impasse. And third, we argue that if the Round maintains its stated aims but moves away from the non-reciprocal special-and-differential treatment norm as the cornerstone of the approach to meeting developing country needs in the WTO, and if developing countries prepare, in markets where they are large, to come to the bargaining table and to negotiate reciprocally with each other and with developing nations, then it might be possible to break the impasse at Doha, to address the latecomers problem, and to deliver trade gains for developing countries.

National Sovereignty in an Interdependent World

What are the sovereign rights of nations in an interdependent world, and to what extent do these rights stand in the way of achieving important international objectives? These two questions rest at the heart of contemporary debate over the role and design of international institutions as well as growing tension between globalization and the preservation of national sovereignty. In this paper, we propose answers to these two questions. We do so by first developing formal definitions of national sovereignty that capture features of sovereignty emphasized in the political science literature. We then utilize these definitions to describe the degree and nature of national sovereignty possessed by governments in a benchmark (Nash) world in which there exist no international agreements of any kind. And with national sovereignty characterized in this benchmark world, we then evaluate the extent to which national sovereignty is compromised by international agreements with specific design features. In this way, we delineate the degree of tension between national sovereignty and international objectives and describe how that tension can be minimized and in principle at times even eliminated through careful institutional design.

Backward Stealing and Forward Manipulation in the WTO

Motivated by the structure of WTO negotiations, we analyze a bargaining environment in which negotiations proceed bilaterally and sequentially under the most-favored-nation (MFN) principle. We identify backward-stealing and forward-manipulation problems that arise when governments bargain under the MFN principle in a sequential fashion. We show that these problems impede governments from achieving the multilateral efficiency frontier unless further rules of negotiation are imposed. We identify the WTO nullification-or-impairment and renegotiation provisions and its reciprocity norm as rules that are capable of providing solutions to these problems. In this way, we suggest that WTO rules can facilitate the negotiation of efficient multilateral trade agreements in a world in which the addition of new and economically significant countries to the world trading system is an ongoing process.

Multilateral Trade Negotiations, Bilateral Opportunism and the Rules of GATT

Trade negotiations occur through time and between the governments of many countries. An important issue is thus whether the value of concessions that a government wins in a current negotiation may be eroded in a future bilateral negotiation to which it is not party. In the absence of rules that govern the bilateral negotiation, we first show that the potential for opportunistic bilateral agreements is indeed severe. We next identify rules of negotiation that serve to protect the welfare of governments that are not participating in the bilateral negotiation. The reciprocal market access' rule ensures that the market access of a non-participating country is unaltered, and we show that this rule eliminates the potential for opportunistic bilateral negotiations. This rule, however, has practical limitations, and so we next consider the negotiation rules that are prominent in GATT practice and discussion. Our main finding is that the two central rules of GATT -- non-discrimination (MFN) and reciprocity -- effectively mimic the reciprocal market access rule, and therefore offer a practical means through which to protect non-participant welfare and thereby eliminate the potential for opportunistic bilateral negotiations.

Collusion over the Business Cycle

We present a theory of collusive pricing in markets subject to business cycle fluctuations. In the business cycle model that we adopt, market demand alternates stochastically between fast-growth (boom) and slow-growth (recession) phases. We provide a complete characterization of the most-collusive prices and show that: (1) the most-collusive prices may be procyclical (countercyclical) when demand growth rates are positively (negatively) correlated through time, and (2) the amplitude of the collusive pricing cycle is larger when the expected duration of boom phases decreases and when the expected duration of recession phases increases. We also offer a generalization of Rotemberg and Saloner's (1986) model, and interpret their findings in terms of transitory demand shocks that occur within broader business cycle phases.

Subsidy Agreements

International disputes over subsidies are increasingly disrupting the world trading system. The creation of the WTO was nearly prevented by disputes in the Uruguay Round of GATT negotiations over the issue of negotiating disciplines on agricultural subsidies, an issue which continues to plague the ongoing Doha Round of WTO negotiations. Ongoing disputes over subsidies that violate existing WTO rules have led to the largest amount of authorized retaliation in GATT/WTO history. Yet the international rules that govern subsidies have received little attention in the form of systematic economic analysis. In this paper we provide a first formal analysis of the international rules that govern the use of subsidies to domestic production (as distinct from export subsidies). Our analysis highlights the impact of the new disciplines on subsidies that were added to GATT rules with the creation of the WTO. Our results suggest that, although GATT subsidy rules were typically viewed as weak and inadequate while the WTO subsidy rules are seen as representing a significant strengthening of multilateral disciplines on subsidies, the key changes introduced by the WTO subsidy rules may ultimately do more harm than good to the multilateral trading system, by undermining the ability of tariff negotiations to serve as the mechanism for expanding market access to more efficient levels.

GATT-Think

We describe recent work on the theory of trade agreements that speaks to the purpose and design of GATT. Our discussion proceeds in three steps. First, we examine the purpose of a trade agreement. In both the traditional economic and the political-economy approaches to the study of trade agreements, the problem for a trade agreement to solve is the excessive protection that arises in the absence of an agreement as a consequence of the terms-of-trade externality. Second, we consider the origin and design of GATT. We note that GATT is a rules-based institution whose origin can be traced to the disastrous economic performance that accompanied the high tariffs of the 1920's and 1930's. Finally, we review the theoretical literature that interprets and evaluates the institutional features found in GATT. We consider in particular whether GATT articles can be interpreted as offering negotiation rules that help governments undo the inefficient restrictions in trade that are caused by the terms-of-trade externality. On the whole, our review suggests that the core principles of GATT indeed may be interpreted in this manner. Specifically, we report findings that indicate that the principles of reciprocity and non-discrimination work in concert to remedy the inefficiency created by the terms-of-trade externality. We also extract a variety of predictions from the literature on enforcement and trade policy, and we argue that these predictions are broadly compatible with both the design of GATT and certain historical experiences in trade-policy conduct. We thus interpret the literature reviewed here as providing a strong presumption for the view that GATT can be understood as an institution whose central principles are well-designed to assist governments in their attempt to escape from a terms-of-trade-driven Prisoners' Dilemma. Our review therefore offers support for the (politically-augmented) terms-of-trade theory as an appropriate framework within which to interpret and evaluate GATT.