4第四章 供求原理(理解市场运行).ppt

* 30 * 30 * 30 * 30 * 27 * In the second bullet point, “output price” just means the price of the good that firms are producing and selling. I have used “output price” here to distinguish it from “input prices.” * Again, the animation here is carefully designed to help make clear that a shift in the supply curve means that there is a change in the quantity supplied at each possible price. If it seems tedious, you can turn it off. In any case, be assured that, by the end of this chapter, the animation of curve shifts will be streamlined and simplified. “Tax return preparation software” means programs like TurboTax by Quicken and TaxCut by HR Block. * 36 * 36 * 36 * 46 * 46 Important note about Event B: The royalties that sellers must pay the artists are part of sellers’ “costs of production.” Typically, this royalty is a fixed amount each time one of the artist’s songs is downloaded. Event B, therefore, describes a reduction in sellers’ “costs of production.” This is an extension of Active Learning exercise 1C, where we saw that a fall in the price of compact discs would cause a fall in demand for music downloads, because the two goods are substitutes. NOTE: Don’t worry that the text on this slide looks garbled in “Normal view” (i.e., edit mode). It works fine in “Slide Show” (i.e., presentation mode). Event B: Sellers of music downloads negotiate a reduction in the royalties they must pay for each song they sell. This event causes a fall in “costs of production” for sellers of music downloads. Hence, the S curve shifts to the right. It’s not necessary to draw a graph here. The answers to steps 1 and 2 should be clear from parts A and B. The answer to step 3 is a combination of the results from A and B. * In the textbook, the conclusion of this chapter offers some very nice elaboration on the second bullet point. There is also an “In the News” box with a very nice article titled “In Praise of Price Gouging.” * * * * 供给与需求的市场力量 * 例子：混合动力汽