우리나라 새우 수입 시장의 탄력성과 충격 반응에 관한 연구 : AIDS, VAR-X, BEKK 모형을 이용하여

다국어 초록 (Multilingual Abstract)

The purpose of this study is to examine the structure and dynamics of the shrimp market by analyzing the demand system, causal relationships, and price volatility between domestic and imported shrimp in Korea. The research is composed of three main analyses.
First, the demand relationship between domestic and imported shrimp was investigated using the AIDS model. The analysis included domestic shrimp and imported shrimp from Vietnam, Ecuador, China and Malaysia. Based on the tests, an unrestricted linear AIDS model was estimated, incorporating quarterly dummy variables and Korea’s GDP as instrumental variables to account for seasonality and endogeneity.
The results indicated that the relationship of domestic and imported shrimp identified as complements or substitutes depending on presence of the income effects. While domestic shrimp compete with similar imported products, imported shrimp supplement domestic supply during periods of excess demand. The relationship among imported shrimp turned out to be both substitutes and complements. The shrimp products with similar consumption patterns show substitution effects, whereas heterogeneous products display complementary effects.
Using instrumental variables, the presence of endogeneity was confirmed, indicating that the estimated elasticities represent bias-corrected measures that appropriately account for endogeneity. Furthermore, the seasonal dummy variables indicated that domestic shrimp consumption expands during main production seasons, whereas the demand for imported shrimp increases during off-seasons.
Second, the causal relationship between domestic and Vietnamese shrimp markets was investigated using the VAR and the VAR-X models, employing data on Vietnamese import price and volume, and domestic producer price and volume. Unit root tests confirmed the stability of the data series, and a four-lag structure was selected based on information criteria. The VAR-X model includes the Korea–Vietnam FTA and the COVID-19 pandemic as exogenous dummy variables.
The results of causality analysis revealed that Vietnamese import price is the leading variable, followed by domestic producer price, domestic production volume, and Vietnamese import volume. After the FTA was implemented, Vietnamese import volumes increased while import prices declined, and domestic producer prices rose. This indicates that FTA deepened market segmentation between the imported (frozen) and domestic (live/fresh) shrimp markets. Meanwhile, the VAR-X model that incorporated the COVID-19 exogenous variable did not yield a significantly improved likelihood.
Comparing impulse response functions of the VAR and the VAR-X model, the results of VAR model showed persistent shocks to import volume, while the VAR-X model incorporating the FTA indicated that shocks converged to zero. This implies that the import market has been stabilized after FTA.
Third, the transmission of price volatility between domestic and imported shrimp markets was investigated using the BEKK multivariate GARCH model. The data series of price (Domestic producer price, Vietnamese import price, Chinese import price) change rate was employed to VAR model and residuals from the VAR model were applied to the BEKK model.
The results showed that all prices were significantly influenced by their own shocks and conditional variances. In particular, Chinese import price affected both domestic producer price and Vietnamese price, serving as a key volatility driver. The results of the asymmetric model were not statistically significant, suggesting that leverage effects are absent in shrimp market.
The impulse response analysis revealed that price volatility generally decreased after the FTA, with weaker market linkages between markets and independent adjustments leading to a more stable market structure. Moreover, the volatility response to the COVID-19 shock was smaller than that of the FTA, indicating that the FTA had a greater structural impact on the shrimp market.
These three sets of analyses—demand structure, causal linkages, and volatility dynamics—collectively provide a stepwise examination of the structural characteristics of the Korean shrimp market. Taken together, the findings indicate that domestic production and import markets are interconnected in complex ways, yet the market has tended to stabilize and become more segmented following the implementation of FTA.
Overall, the findings of this study provide empirical evidence for understanding the interactions between domestic production and import markets and can serve as a reference for future trade negotiations and policymaking. In addition, they underscore the importance of considering both domestic production and import simultaneously to ensure the stability of shrimp supply and market prices.

목차 (Table of Contents)

• Ⅰ. 서론 1
• 1. 연구 배경 및 목적 1
• 2. 연구 방법 및 구성 4
• 3. 선행연구 검토 10
• Ⅱ. 새우 수급 현황 분석 22
• 1. 세계 새우 생산 및 교역 현황 22
• 2. 국내 새우 생산 현황 25
• 3. 새우 교역 동향 31
• 4. 우리나라 새우 수급 현황 및 연구 범위 43
• Ⅲ. AIDS 모형을 이용한 국내산 및 수입산 새우 수요체계 분석 46
• 1. 이론적 배경 46
• 2. 실증분석 48
• 3. 소결 60
• Ⅳ. VAR-X 모형을 이용한 베트남산 새우 수입과 국내 새우 생산 간의 동태적 인과관계 분석 62
• 1. 이론적 배경 62
• 2. 실증분석 67
• 3. 소결 96
• Ⅴ. BEKK 모형을 이용한 새우 수입시장과 국내 생산시장의 가격 변동성 전이 효과 및 충격반응 분석· 98
• 1. 이론적 배경 98
• 2. 실증분석 101
• 3. 소결 117
• Ⅵ. 요약 및 결론 119
• 1. 연구 요약 119
• 2. 정책적 시사점 123
• 3. 연구의 의의와 향후 과제 125