環保時尚的行銷，水平生產協調與國際貿易

環保商品不但具有一般消費的價值，也有炫耀性的功能。非環保商品的消費對環保商品的需求有正向的外溢性。愈多非環保商品被消費，環保商品的炫富效果愈強。商品的定價並非如市場區隔時依單一市場的需求彈性而定，非環保商品的外溢性也是決定均衡價格重要的因素之一。除此之外，政府環保技術的投入不但須考量環保品代替非環保品所降低的社會成本，也須注意炫富效果導致非環保品消費的產量的增加，以致社會成本的增加。環保商品的廠商與非環保商品的廠商是否參與水平合併產出的協調依國際市場競爭型態及非環保商品的外溢性而定。當國際市場為寡占數量競爭時，這兩類出口廠商會參與水平協調決定產品的出口量。政府的最適策略貿易政策依然是出口補貼；而非環保商品的外溢性會加強出口補貼政策。然而當國際市場為寡占價格競爭而非環保商品外溢性並不顯著時，出口廠商並不會參與水平協調。政府的最適策略貿易政策依非環保商品的外溢性強度而定。當外溢性弱時，政府的政策是對出口課稅，但是外溢性很強時，政府對非環保品的出口為補貼。

關鍵字

外溢性；水平合併；數量競爭；價格競爭；補貼

並列摘要

Green(environmentally friendly) goods not only has the value of consumption sourced from its own original function, but also has the conspicuous features that can be used to signal prestige. The consumption of non-green (environmentally unfriendly) goods has a positive spillover effect on the demand for green goods. The more non-green are consumed, the stronger the Veblen effect of green goods is. The pricing of green goods is determined by their elasticity of demand that is affected by the consumptions of both goods. The spillover of non-green goods is one of the key factors to determine the equilibrium price of green goods. In addition, government’s expenditure in developing environmentally friendly technologies is also associated with it. The producers of green goods and non-green goods will coordinate of their outputs when the international market is in quantity competition. In this case, subsidizing exports still is the optimal strategic trade policies and the spillover enhances them. On the one hand, if the Veblen effect is weak, the producers of green goods and non-green goods will not coordinate of their outputs when the international market is in prices competition. On the other hand, if the Veblen effect is strong, it is not necessary for the government to impose taxes on the export as what is claimed in Eaton and Grossman (1986).