tailieunhanh - Tài liệu trung cấp môn Kinh tế vi mô bằng tiếng Anh - Phần 16

Tài liệu tham khảo Tài liệu trung cấp môn Kinh tế vi mô bằng tiếng Anh gồm 41 phần giúp sinh viên khoa kinh tế học tốt môn Kinh tế vi mô. Tài liệu này là phần 16 giới thiệu về " Nhu cầu thị trường - Market demand " | CHAPTER 15 MARKET DEMAND We have seen in earlier chapters how to model individual consumer choice. Here we see how to add up individual choices to get total market demand. Once we have derived the market demand curve we will examine some of its properties such as the relationship between demand and revenue. From Individual to Market Demand Let us use to represent consumer z s demand function for good 1 and for consumer t s demand function for good 2. Suppose that there are n consumers. Then the market demand for good 1 also called the aggregate demand for good 1 is the sum of these individual demands over all consumers n The analogous equation holds for good 2. FROM INDIVIDUAL TO MARKET DEMAND 267 Since each individual s demand for each good depends on prices and his or her money income the aggregate demand will generally depend on prices and the distribution of incomes. However it is sometimes convenient to think of the aggregate demand as the demand of some representative consumer who has an income that is just the sum of all individual incomes. The conditions under which this can be done are rather restrictive and a complete discussion of this issue is beyond the scope of this book. If we do make the representative consumer assumption the aggregate demand function will have the form Xi pi .p2-AT . where M is the sum of the incomes of the individual consumers. Under this assumption the aggregate demand in the economy is just like the demand of some individual who faces prices pi P2 and has income M. If we fix all the money incomes and the price of good 2 we can illustrate the relation between the aggregate demand for good 1 and its price as in Figure . Note that this curve is drawn holding all other prices and incomes fixed. If these other prices and incomes change the aggregate demand curve will shift. The market demand curve. The market demand curve is the sum of the individual demand curves. For example if goods 1 and 2 are substitutes then we know .