本研究擬以ECFA簽定後涉及的魚種中選擇石斑活魚作為本研究的研究對象,以價格傳遞的VAR(vector autoregressive model,以下簡稱VAR)模型分析台灣石斑魚國內消費批發價格與出口價格的連動關係,並說明關稅下降的外生變動對價格的衝擊及可能調整的方向及速度,最後以經濟剩餘模型(economic surplus model)估算關稅下降對石斑魚國內消費者、生產者及貿易商產生福利變動的大小及分配。共整合(cointegration)分析的結果顯示,石斑魚消費批發市場價格與出口價格間具有長期均衡正向關係,結構變化檢定的結果亦顯示兩價格序列分別在2008年10月及2010年4月為結構變化分界點,後者為海峽兩岸活魚運搬船直航起始時間,顯見此事件對活魚出口價格的提升有顯著影響。另外,VAR模型顯示兩岸活魚運搬船直航後,前期石斑魚出口價格對本期石斑魚消費價格的影響由無影響轉為有正且顯著影響,消費批發價格對出口價格有正且顯著影響,前期石斑魚出口價格對本期石斑魚出口價格,也在兩岸活魚直航後,影響顯著加大。經濟剩餘模型估算的結果則顯示,關稅下降對石斑魚國內消費者不利,但生產者及貿易商得利,若以2011年的平均出口價格估算,ECFA對石斑魚產業整體的福利一年約為新台幣14億元。
Grouper (live fish) is selected as the research object involved after the signing of the ECFA. Using VAR (vector autoregressive model) model to analysis the price transmission and dynamic relationship between Taiwan Grouper wholesale prices and it export price to China. Size and distribution of welfare changes for domestic consumers, producers and traders are estimated, because of signed ECFA.The results showed that the domestic wholesale market prices and export prices of Grouper has a long-run positive relationship, and the the cut-off point test of structural changes of two prices also indicated in October 2008 and April 2010, respectively. The latter is the start time of direct shipping of live aquacultural fish between Taiwan and China, the event shown significantly positive impact on export price. In addition, after the direct shipping, the impact of previous Grouper export price on its current wholesale price has turn to significantly positive. Wholesale price also has a positive and significant impact on its export prices; the impact of previous Grouper export prices to current export prices significantly increase after the direct shipping. Economic surplus model showed that decline in tariffs decrease the welfare of domestic consumers, but producers and traders' welfare are better off. In term of the average export price of year 2011, the overall welfare of signed ECFA for all Grouper stakeholder is approximately NT$ 1.4 billion per year.