經(jīng)濟學(xué)原理曼昆06.ppt

1、,第6章：供給、需求 與政府政策,Chapter 6,供給，需求和政府政策,在一個自由的，無管制的市場體系中，均衡的價格和交易數(shù)量是由市場的力量所建立的 In a free, unregulated market system, market forces establish equilibrium prices and exchange quantities. 當(dāng)均衡狀態(tài)是有效的時候，每個人才與可能被滿足。 While equilibrium conditions may be efficient, it may be true that not everyone is satisfied.

2、 經(jīng)濟學(xué)家的一個角色就是運用理論來支持政策的發(fā)展 One of the roles of economists is to use their theories to assist in the development of policies,價格上限與價格下限Price Ceilings & Price Floors,Price Ceiling 價格上限 指某一物品出售的法定最高價格 A legal maximum on the price at which a good can be sold Price Floor 價格下限 指某一物品出售的法定最低價格 A legal minimum

3、on the price at which a good can be sold.,價格上限,當(dāng)政府強制實行價格上限時 可能出現(xiàn)兩種結(jié)果: 價格上限如果設(shè)在均衡價格之上，就是沒有約束力的. The price ceiling is not binding if set above the equilibrium price 價格上限如果設(shè)在均衡價格之下，從而導(dǎo)致短缺，就是具有約束力的. The price ceiling is binding if set below the equilibrium price, leading to a shortage.,有價格上限時的市場,(a) 沒有限

4、制作用的價格上限,冰激凌蛋卷的數(shù)量,0,冰激凌蛋卷的價格（美元）,均衡價格,有限制作用的價格上限,Copyright2003 Southwestern/Thomson Learning,(b) 有限制作用的價格上限,冰激凌蛋卷的數(shù)量,0,冰激凌蛋 卷的價格,價格上限效應(yīng)Effects of Price Ceilings,有約束力的價格上限創(chuàng)造 . 短缺 因為 QD QS. 范例: 20世紀(jì)70年代的汽油短缺 Gasoline shortage of the 1970s 非價格配給 范例: 排長隊, 賣方實施的歧視 Long lines, discrimination by sellers,19

5、73年，石油輸出國組織OPEC提高了世界石油市場的原油價格。由于原油是用于生產(chǎn)汽油的主要投入，較高的石油價格減少了汽油供給. 是什么導(dǎo)致了人們排隊加油呢？,案例研究：加油站前的長隊,經(jīng)濟學(xué)家把它歸咎于限制石油公司對汽油可以收取的價格的政府管制,有價格上限的汽油市場,Copyright2003 Southwestern/Thomson Learning,(a) 汽油的價格上限沒有限制性,汽油數(shù)量,0,汽油價格,有價格上限的汽油市場,Copyright2003 Southwestern/Thomson Learning,(b) 汽油的價格上限有限制性,汽油數(shù)量,0,汽油價格,租金控制Rent Co

6、ntrol,租金控制就是對房東向租戶索取的房租制定最高價格水平線. Rent controls are ceilings placed on the rents that landlords may charge their tenants. 租金控制政策的目標(biāo)是通過使住房租金變得讓大多數(shù)人能夠支付得起，從而幫助窮人。 The goal of rent control policy is to help the poor by making housing more affordable. 有位經(jīng)濟學(xué)家把租金控制說成是“除了轟炸之外摧毀城市的最佳方式”。 One economist calle

7、d rent control “the best way to destroy a city, other than bombing.”,短期中的租金控制Rent Control in the Short Run.,公寓數(shù)量,0,公寓的 出租價格,需求,供給,公寓的供給與需求是相對缺乏彈性的,長期中的租金控制Rent Control in the Long Run.,公寓數(shù)量,0,公寓的 出租價格,需求,供給,因為公寓的供給與需求更加具有彈性.,租金控制引起更大的短缺,價格下限Price Floors,當(dāng)政府強制實行價格下限時 可能出現(xiàn)兩種結(jié)果: 價格下限如果設(shè)在均衡價格之下，就是沒有約束力的

8、. The price floor is not binding if set below the equilibrium price. 價格下限如果設(shè)在均衡價格之下，從而導(dǎo)致過剩，就是具有約束力的. The price floor is binding if set above the equilibrium price, leading to a surplus.,有價格下限的市場,Copyright2003 Southwestern/Thomson Learning,(a) 沒有限制性的價格下限,冰激凌蛋卷的數(shù)量,0,冰激凌蛋卷 的價格,有價格下限的市場,Copyright2003 So

9、uthwestern/Thomson Learning,（b）有限制性的價格下限,冰激凌蛋卷的數(shù)量,0,冰激凌 蛋卷的價格,價格下限的效應(yīng),有約束力的價格下限引起 . . . 過剩，因為 QS QD. a surplus because QS QD. 非價格配給 是一種利用歧視標(biāo)準(zhǔn)的可替換的商品配給機制. nonprice rationing is an alternative mechanism for rationing the good, using discrimination criteria. 范例: 最低工資, 農(nóng)業(yè)價格扶持 The minimum wage, agricultu

10、ral price supports,最低工資,價格下限的一個例子是最低工資。最低工資法設(shè)定了任何雇主雇傭勞動力時所付的最低價格。 An important example of a price floor is the minimum wage. Minimum wage laws dictate the lowest price possible for labor that any employer may pay.,最低工資如何影響勞動力市場,Copyright2003 Southwestern/Thomson Learning,勞動力數(shù)量,工資,0,最低工資 The Minimum

11、Wage,勞動力數(shù)量,0,工資,勞動力需求,勞動力供給,存在最低工資的勞動力市場,稅收,政府通過征收稅收來為公共項目集資。 Governments levy taxes to raise revenue for public projects.,向買者或者賣者征稅如何影響市場結(jié)果？How Taxes on Buyers (and Sellers) Affect Market Outcomes,稅收并不鼓勵市場行為 Taxes discourage market activity. 當(dāng)對一個物品征稅時，銷售量下降 When a good is taxed, the quantity sold i

12、s smaller. 買者和賣者共同負(fù)擔(dān)稅收 Buyers and sellers share the tax burden.,彈性與稅收歸宿Elasticity and Tax Incidence,稅收歸宿是指稅收負(fù)擔(dān)如何在市場參與者之間分擔(dān)。 Tax incidence is the manner in which the burden of a tax is shared among participants in a market.,稅收,稅收歸宿（Tax incidence） 是對由誰來承擔(dān)稅收負(fù)擔(dān)的研究. Tax incidence is the study of who bear

13、s the burden of a tax. 稅收引起市場均衡的變化. Taxes result in a change in market equilibrium 無論稅收是向誰征收的，購買者都要支付得更多，而出售者則得到較少的收入 Buyers pay more and sellers receive less, regardless of whom the tax is levied on.,對買者征稅,Copyright2003 Southwestern/Thomson Learning,冰激凌蛋卷的數(shù)量,0,冰激凌 蛋卷的價格,對賣者征稅,Copyright2003 Southwes

14、tern/Thomson Learning,冰激凌蛋卷的數(shù)量,I,0,冰激凌 蛋卷的價格,工資稅,勞動力數(shù)量,0,工資,勞動力需求,勞動力供給,彈性與稅收歸宿Elasticity and Tax Incidence,稅收負(fù)擔(dān)應(yīng)該以何種比例分擔(dān)？ In what proportions is the burden of the tax divided? 稅收對買者的影響相對于賣者是什么樣的？ How do the effects of taxes on sellers compare to those levied on buyers? 這些問題的答案依賴于需求彈性和供給彈性 The answe

15、rs to these questions depend on the elasticity of demand and the elasticity of supply.,稅收負(fù)擔(dān)如何分?jǐn)?Copyright2003 Southwestern/Thomson Learning,數(shù)量,0,價格,(a) 供給富有彈性，需求缺乏彈性,稅收負(fù)擔(dān)如何分?jǐn)?Copyright2003 Southwestern/Thomson Learning,數(shù)量,0,價格,(b)供給缺乏彈性，需求富有彈性,稅收究竟如何分?jǐn)偅?稅收負(fù)擔(dān)更多的落在缺乏彈性的市場一方上 The burden of a tax falls more heavily on the side of the market that is less elastic.,ELASTICITY AND TAX INCIDENCE,小結(jié),價格控制包