No abstract

Korea replaced its rice import quota with a tariff rate quota (TRQ) in 2015. A structural model representing the Korean rice market is developed to evaluate this new trade policy and examine the possibility of Korean rice imports under uncertainty. Results indicate that rice imports in excess of the current TRQ quantity are unlikely for a range of market conditions. Two scenarios, which are the over-quota tariff rate reduction and the TRQ quantity expansion, show how the market responds to policy changes. In addition, Korean rice imports are sensitive to consumer preferences for different rice types.

Soybean production and trade in the U.S. and Brazil are seasonal. Our research question is whether the seasonal tendencies cause the price relationship between U.S. and Brazilian soybean prices. Therefore, the objective is to test for seasonality in the price transmission between the U.S. and Brazil soybean prices using the seasonal regime-dependent vector error correction model (VECM). Our results show that the speed of the adjustment for the U.S. soybean price in the first half of the year is greater than the speed of the adjustment for the Brazilian soybean price. However, the pattern of their responses becomes the reverse in the second half of the year. The component share calculated by the result of the VECM with seasonal effects indicates that the U.S. dominates the world soybean market during the second half of the year while Brazil is dominant in the soybean market in the first half of the year. These results give us an important finding that we could not find using the VECM without seasonal effects. Finally, our results imply that the seasonal pattern of production in the U.S. and Brazil could cause the sustainability of the supply chain in the world soybean market.

We investigate how a combination of the Sanitary and Phytosanitary (SPS) measure and product differentiation affects beef trade and the consequences for the US-EU hormonetreated beef trade dispute. We develop a partial equilibrium model to represent the global beef markets and product differentiation between non-hormone-treated beef, hormone-treated beef, and other beef. The results show that removing the SPS measure increases EU hormone-treated beef imports from the US and Canada and decrease beef consumption. In addition, EU hormone-treated beef consumption and imports can be related to a few key indicators of product differentiation. The framework we develop can estimate EU hormonetreated beef consumption and imports based on a minimum of parameters relating to product differentiation, thereby providing useful applied economic analysis of a key trade measure.

This study analyzed the effect of the sensitivity of news related to onions on producers' decision-making on cultivation areas and market supply and demand. We collected onion-related article data and derived the sentiment index through sentiment analysis using neural networkbased learning. We estimated the cultivation area function, including the sentiment index we made. We analyzed the impact of news sensitivity on the onion market by constructing an onion market supply and demand model. Then, we gave a sentiment index shock to the cultivation area to examine the impact on the onion market. We also explored the sensitivity analysis to emphasize the news in June, July, and August plays an important role in the supply side. To the best of our knowledge, our approach using sentiment index in the agricultural model is the first trial. Therefore, our study can introduce an approach to improve the accuracy of modeling for agriculture and apply it to the area of agricultural economics.