2011年-WTO世界贸易组织_The_Value_of_Bindings_16页_727kb

报告摘要

Summary of "The Value of Bindings" by Marc Bacchetta and Roberta Piermartini

Core Content

This paper investigates the value of tariff bindings in the context of the World Trade Organization (WTO) and their impact on trade policy volatility. It focuses on whether the commitment to a certain tariff level (i.e., a binding) reduces the uncertainty and variability in trade policy, even when the actual applied tariff is lower than the bound rate.

The authors argue that tariff bindings provide a stabilizing effect on trade policy, reducing the likelihood of tariff increases and increasing the likelihood of tariff decreases. This is due to the commitment effect, which makes governments more predictable in their trade policy actions, thereby lowering the risk for exporters and enhancing market access stability.

Main Views

Binding tariffs reduce the scope for discretionary use of tariffs and thus contribute to trade policy predictability.
The "water" in tariffs (the gap between bound and applied rates) can be a source of flexibility in WTO commitments, allowing countries to adjust tariffs without violating their commitments.
Empirical evidence suggests that:
- Countries with bound tariffs are more likely to decrease and less likely to increase their applied tariffs.
- The taming effect of bindings decreases as the level of water increases.
Political economy factors and economic cycles influence the variability of tariffs, but the effect of bindings remains robust even after controlling for these variables.
Regional trade agreements (RTAs) and multilateral commitments are complementary in reducing tariff increases and increasing tariff reductions.

Key Findings

Tariff variability is significantly affected by the binding status of tariff lines.
Bound lines have a lower average tariff compared to unbound lines, and this holds true across different levels of water.
The variability of bound lines is higher than that of unbound lines, suggesting that while bindings reduce the risk of increases, they do not necessarily reduce the overall variability of trade policy.
The probability of tariff decreases is significantly higher for bound lines than for unbound lines, particularly when the water level is low.
When water levels are high, the stabilizing effect of bindings is diminished, implying that the value of bindings is related to the depth of the water.

Methodology and Data

The authors use a database of applied tariffs covering over 100 countries from 1996 to 2009, at the 6-digit HS level.
They focus on ad valorem tariffs, excluding non-ad valorem ones to isolate the effect of bindings.
The data includes:
- Bound and applied tariff lines.
- Tariff changes over time.
- Political economy controls such as sector size, lobbying pressures, and competition levels.
- Economic cycle controls such as GDP growth and import growth.

Empirical Analysis

The authors estimate the probability of tariff increases and decreases using a Logit model.
They find that:
- Binding status has a negative effect on the probability of tariff increases.
- Binding status has a positive effect on the probability of tariff decreases.
- Water lag (the level of water in the previous year) has a positive effect on the probability of tariff increases.
The results are robust to the inclusion of political economy and economic cycle controls.

Conclusion

The value of bindings lies in their ability to reduce trade policy uncertainty and stabilize tariff levels, even when the applied tariff is below the bound rate.
The effect of bindings is stronger when the water level is low, suggesting that tighter bindings lead to more predictable trade policies.
The presence of bindings is associated with lower volatility in trade policy, which can have positive welfare implications for both importing and exporting countries.