西方經(jīng)濟(jì)學(xué)課件：第17章信息不對(duì)稱的市場(chǎng)

1、第 17 章信息不對(duì)稱的市場(chǎng)信息不對(duì)稱的市場(chǎng)Chapter 17Slide 2本章要討論的問題本章要討論的問題質(zhì)量不確定性與檸檬市場(chǎng)市場(chǎng)信號(hào)道德風(fēng)險(xiǎn)委托代理問題Chapter 17Slide 3本章要討論的問題本章要討論的問題一體化企業(yè)的管理激勵(lì)問題勞動(dòng)力市場(chǎng)的信息不對(duì)稱: 效率工資理論Chapter 17Slide 4引言引言我們將研究不完全信息對(duì)資源配置和價(jià)格機(jī)制所產(chǎn)生的影響。Chapter 17Slide 5質(zhì)量不確定與檸檬市場(chǎng)質(zhì)量不確定與檸檬市場(chǎng)在購買一輛二手車時(shí)，由于信息不完全，將增加購買的風(fēng)險(xiǎn)并降低消費(fèi)者的效用；Chapter 17Slide 6二手車市場(chǎng)l假定u買賣雙方都能鑒別高

2、質(zhì)量和低質(zhì)量的車；u將會(huì)出現(xiàn)兩個(gè)市場(chǎng)；質(zhì)量不確定與檸檬市場(chǎng)質(zhì)量不確定與檸檬市場(chǎng)檸檬問題檸檬問題PHPLQHQLSHSLDHDL5,00050,00050,000買賣雙方能鑒別車的質(zhì)量時(shí)，買賣雙方能鑒別車的質(zhì)量時(shí)，將出現(xiàn)高質(zhì)量和低質(zhì)量?jī)蓚€(gè)市場(chǎng)將出現(xiàn)高質(zhì)量和低質(zhì)量?jī)蓚€(gè)市場(chǎng)10,000DLDMDM75,00025,000由于信息不對(duì)稱，消費(fèi)者無法確定車的質(zhì)量，他們將降低由于信息不對(duì)稱，消費(fèi)者無法確定車的質(zhì)量，他們將降低對(duì)二手車質(zhì)量的期望對(duì)二手車質(zhì)量的期望 。 Demand for low and high quality used cars shifts to DM.DLMDLMThe increa

3、se in QLreduces expectations anddemand to DLM. The adjustment processcontinues until demand = DL. Chapter 17Slide 8The Market for Used CarslWith asymmetric information:uLow quality goods drive high quality goods out of the market.uThe market has failed to produce mutually beneficial trade.uToo many

4、low and too few high quality cars are on the market.uAdverse selection occurs; the only cars on the market will be low quality cars.Quality Uncertaintyand the Market for LemonsChapter 17Slide 9Implications of Asymmetric InformationMedical InsurancelQuestionuIs it possible for insurance companies to

5、separate high and low risk policy holders?lIf not, only high risk people will purchase insurance.lAdverse selection would make medical insurance unprofitable.The Market for InsuranceChapter 17Slide 10Implications of Asymmetric InformationAutomobile InsurancelQuestionsuWhat impact does asymmetric inf

6、ormation and adverse selection have on insurance rates and the delivery of automobile accident insurance?uHow can the government reduce the impact of adverse selection in the insurance industry?The Market for InsuranceChapter 17Slide 11Implications of Asymmetric InformationThe Market for CreditlAsym

7、metric information creates the potential that only high risk borrowers will seek loans.lQuestionuHow can credit histories help make this market more efficient and reduce the cost of credit?Chapter 17Slide 12Implications of Asymmetric InformationThe Importance of Reputation and StandardizationlAsymme

8、tric Information and Daily Market DecisionsuRetail salesuAntiques, art, rare coinsuHome repairsuRestaurantsChapter 17Slide 13Implications of Asymmetric InformationQuestionlHow can these producers provide high-quality goods when asymmetric information will drive out high-quality goods through adverse

9、 selection.lAnsweruReputationChapter 17Slide 14Implications of Asymmetric InformationQuestionlWhy do you look forward to a Big Mac when traveling even though you would never consider buying one at home.Holiday Inn once advertised “No Surprises” to address the issue of adverse selection.Chapter 17Sli

10、de 15Lemons in Major League BaseballAsymmetric information and the market for free agentslIf a lemons market exists, free agents should be less reliable (disabled) than renewed contracts.Chapter 17Slide 16Player DisabilityAll Players4.7312.55165.4Renewed players4.769.68103.4Free agents4.6717.23268.9

11、Days Spent on Disabled List per SeasonPrecontractPostcontract Percentage ChangeChapter 17Slide 17FindingslDays on the disabled list increase for both free agents and renewed players.lFree agents have a significantly higher disability rate than renewed players.lThis indicates a lemons market.Lemons i

12、n Major League BaseballChapter 17Slide 18QuestionlIf you are a team owner, what steps would you take to reduce the asymmetric information for free agents?Lemons in Major League BaseballChapter 17Slide 19Market SignalingThe process of sellers using signals to convey information to buyers about the pr

13、oducts quality helps buyers and sellers deal with asymmetric information.Chapter 17Slide 20Market SignalingStrong SignallTo be effective, a signal must be easier for high quality sellers to give than low quality sellers.lExampleuHighly productive workers signal with educational attainment level. Cha

14、pter 17Slide 21Market SignalingA Simple Model of Job Market SignalinglAssumeuTwo groups of workerslGroup I: Low productivity-AP & MP = 1lGroup II: High productivity-AP & MP = 2lThe workers are equally divided between Group I and Group II-AP for all workers = 1.5Chapter 17Slide 22Market Signa

15、lingA Simple Model of Job Market SignalinglAssumeuCompetitive Product MarketlP = $10,000lEmployees average 10 years of employmentlGroup I Revenue = $100,000 (10,000/yr. x 10)lGroup II Revenue = $200,000 (20,000/yr. X 10)Chapter 17Slide 23Market SignalingWith Complete Informationlw = MRPlGroup I wage

16、 = $10,000/yr.lGroup II wage = $20,000/yr.With Asymmetric Informationlw = average productivitylGroup I & II wage = $15,000Chapter 17Slide 24Market SignalingSignaling With Education to Reduce Asymmetric Informationly = education index (years of higher education)lC = cost of attaining educational

17、level ylGroup I-CI(y) = $40,000ylGroup II-CII(y) = $20,000yChapter 17Slide 25Market SignalingSignaling With Education to Reduce Asymmetric InformationlAssume education does not increase productivitylDecision Rule:uy* signals GII and wage = $20,000uBelow y* signals GI and wage = $10,000SignalingYears

18、 ofCollegeValue ofCollegeEduc.0$100KValue ofCollegeEduc.Years ofCollege1234560123456$200K$100K$200KGroup IGroup IICI(y) = $40,000yOptimal choice of y for Group IHow much educationshould a person obtain?The education decisionis based on benefits/costcomparison.B(y)B(y)y*y*B(y) = increase inwage assoc

19、iated witheach level of educationCII(y) = $20,000yOptimal choice of y for Group ISignalingYears ofCollegeValue ofCollegeEduc.0$100KValue ofCollegeEduc.Years ofCollege1234560123456$200K$100K$200KCI(y) = $40,000yOptimal choice of y for Group IB(y)B(y)y*y*Benefits = $100,000CostCI(y) = 40,000y$100,000

20、2.5Choose no educationCII(y) = $20,000yOptimal choice of y for Group IBenefits = $100,000CostCII(yO)= 20,000y$100,000$20,000y*y* Qf ;B = .3Qf + .2(Q - Qf)uIf Q Qf ;B = .3Qf - .5(Qf - Q)Chapter 17Slide 62Incentive Design in an Integrated FirmOutput(units per year)2,0004,0006,00010,000010,00020,00030,

21、00040,000Bonus($ peryear)8,000If Qf = 30,000,bonus is $6,000,the maximumamount possible.Qf = 30,000Qf = 10,000If Qf = 10,000,bonus is $5,000Qf = 20,000If Qf = 20,000,bonus is $4,000Chapter 17Slide 63Asymmetric Information in Labor Markets: Efficiency Wage TheoryIn a competitive labor market, all who

22、 wish to work will find jobs for a wage equal to their marginal product.lHowever, most countries economies experience unemployment.Chapter 17Slide 64The efficiency wage theory can explain the presence of unemployment and wage discrimination.lIn developing countries, productivity depends on the wage

23、rate for nutritional reasons.Asymmetric Information in Labor Markets: Efficiency Wage TheoryChapter 17Slide 65The shirking model can be better used to explain unemployment and wage discrimination in the United States.lAssumes perfectly competitive marketslHowever, workers can work or shirk.lSince pe

24、rformance information is limited, workers may not get fired.Asymmetric Information in Labor Markets: Efficiency Wage TheoryChapter 17Slide 66Without shirking, the market wageis w*, and full-employment exists at L*Demand forLaborw*L*SLUnemployment in a Shirking ModelQuantity of LaborWageNo-ShirkingCo

25、nstraintThe no-shirkingconstraint givesthe wage necessaryto keep workers from shirking.weLeAt the equilibrium wage, We the firm hires Le workerscreating unemployment of L* - Le.Chapter 17Slide 67Efficiency Wages at Ford Motor CompanyLabor turnover at Ford l1913: 380%l1914: 1000%uAverage pay = $2 - $3uFord