第一 二讲 微观经济学CH1 2 3 4课件.ppt

* The lessons illustrated by this international trade example also apply to trade between two individual producers. Note that this chapter in the textbook does the reverse: It develops the lessons in the context of an example involving two individual producers, and then states that the lessons also apply to international trade. So, between this PowerPoint and the textbook chapter, students will see the same concepts and lessons developed in two different but entirely consistent approaches and examples. The example here is highly contrived and unrealistic in order to illustrate complex concepts as simply as possible. The example has some qualities that make it especially valuable: * The two goods are fundamentally different (one is agricultural, the other manufactured), which makes gains from trade based on comparative advantage very likely. An example using more similar goods, say laptop computers and MP3 players, would not be appropriate for this chapter because it would more likely give rise to inter-industry trade, and the gains would likely arise from a source other than comparative advantage (probably increasing returns to scale). * In the example here, it turns out that the U.S. has an absolute advantage in both goods, yet both countries gain from trade. Students see, therefore, that comparative advantage, not absolute advantage, is what’s necessary for trade to be mutually beneficial. * In the real world, one often sees gains from trade based on comparative advantage occurring between countries that are very different – such as between rich industrialized countries and poor developing countries. This example shows that trade based on comparative advantage can also occur between countries that are at similar levels of industrialization and income. (Of course, the U.S. and Japan are very different; but they are far more similar than are, say, the U.S. and Botswana.) * If you just covered Chapter 2, point out to your students that the U.S. PPF