2020年10月，党的十九届五中全会提出深化国资国企改革，做强做优做大 国有资本和国有企业。然而，国有企业因产权性质的特殊性，内部治理过程中始 终存在所有者缺位、政企不分、管理机制不健全等问题，严重影响企业的投资决 策和经营效率。针对国有企业存在的问题，十八届三中全会首次提出积极发展混 合所有制经济，促进国有资产保值增值。近期“双百行动”、“区域综改试验”、 “科改示范行动”、《国企改革三年行动方案》等一系列改革措施落地，国企混 改工作纵深推进，全面提速。本文从投资效率视角深入研究混合所有制改革的经 济效应，对于推进新时代混合所有制改革，推行国企效率型运行机制以及完善企 业治理体系具有深远意义。 本文首先对相关文献进行回顾和梳理，在理论分析的基础上选取2013-2019 年实施混改的国有上市公司作为研究样本，手工收集整理年报披露的前十大股东 性质及股权占比，从股权结构维度构建混合所有制改革的代理变量，并运用修正 后的Richardson（2006）预期投资模型衡量投资效率，从“质”与“量”的双重 视角研究国有上市企业混改对投资效率的影响和作用机制。研究发现：（1）国 有上市企业非效率投资问题突出，相对于投资不足，国有上市公司投资过度问题 更严重。（2）国有上市公司混合所有制改革能够提升企业投资效率。（3）国有 上市公司混合所有制改革能够降低企业代理成本。（4）国有上市公司代理成本 越高，投资效率越低。（5）代理成本在混合所有制改革对投资效率的影响中发 挥中介作用。最后，基于研究结论本文提出发展混合所有制改革、优化公司治理 以及调整投资策略和监管制度等建议。 关键词：混合所有制改革，国有上市公司，投资效率，代理成本 III Abstract InOctober2020,therequirementofdeepenthereformofstate-ownedassets, strengthenstate-ownedenterpriseswasproposedbyTheFifthPlenarySessionofthe NineteenthCentralCommitteeoftheParty.However,thespecialnatureofproperty rightsofstate-ownedenterpriseshascausedproblemssuchastheabsenceofowners, thelackofseparationofgovernmentandenterprises,andtheimperfectmanagement mechanismincorporategovernance,whichseriouslyaffectoperatingefficiency, investmentdecision-making,andthedevelopmentofthestate-ownedbusiness.In responsetotheproblemsofstate-ownedenterprises,fromthefirstproposalofthe ThirdPlenarySessionofthe18thCentralCommitteetoactivelydevelopa mixed-ownershipeconomy,totherecentaseriesofreformmeasures,suchas"Double HundredAction","RegionalComprehensiveReformExperiment","ScienceReform Demonstration"and"Three-yearActionPlanfortheReformofState-owned Enterprises",themixedreformofstate-ownedenterpriseswillbeacceleratedinan all-roundway.Thispaperstudiestheeconomiceffectsofmixedownershipreform fromtheperspectiveofinvestmentefficiency,whichisoffar-reachingsignificance foradvancingmixedownershipreforminthenewera,implementingefficient state-ownedenterpriseoperatingmechanisms,andimprovingcorporategovernance systems. Thisarticlereviewsandsortsouttherelevantliterature.Basedontheoretical analysis,selects2013-2019state-ownedlistedcompaniesimplementingmixedreform astheresearchsample,manuallyjudgeandsortouttheoriginalmaterialsofthetop tenshareholdersofstate-ownedlistedcompaniesfromregularreportsandofficial websitesofthefinancialindustry,distinguishesthenatureofcapitalandthe proportionofequity,constructsproxyvariablesformixedownershipreform,and usetherevisedRichardson(2006)investmentefficiencymodel.Fromthedual perspectivesof"quality"and"quantity",itexplorestheimpactofmixedreformof state-ownedenterprisesoninvestmentefficiency.Theresearchfoundsthat:(1)The problemofinefficientinvestmentinstate-ownedlistedcompaniesisprominent, Comparedwithunder-investment,theproblemofover-investmentinstate-owned enterprisesismoreserious.(2)Themixedownershipreformofstate-ownedlisted companiescanimprovetheefficiency.(3)Themixedownershipreformof state-ownedlistedcompaniescanreducecorporateagencycosts.(4)Thehigherthe agencycostofstate-ownedlistedcompanies,thelowertheinvestmentefficiency.(5) IV Agencycostsplayanintermediaryroleintheimpactofmixedownershipreformon investmentefficiency.Finally,Basedontheresearchconclusions,thisarticleputs forwardsuggestionsfordevelopingmixedownershipreformsandoptimizing corporategovernance，adjustinginvestmentstrategiesandregulatorysystems. Keywords:Mixedownershipreform,State-ownedlistedenterprises, Investmentefficiency,Agencycosts V 目录 声明..........................................................................................................I 摘要........................................................................................................................II Abstract....................................................................................................................III 第一章绪论............................................................................................................1 一、研究背景与意义............................................................................................1 （一）研究背景............................................................................................1 （二）研究意义............................................................................................3 二、文献综述........................................................................................................3 （一）混合所有制改革相关研究................................................................3 （二）投资效率影响因素研究....................................................................5 （三）代理成本影响因素研究....................................................................6 （四）文献评述............................................................................................7 三、研究内容与方法............................................................................................7 （一）研究内容............................................................................................7 （二）研究方法............................................................................................9 四、本文的创新之处............................................................................................9 第二章概念界定与理论基础.........................................................................11 一、概念界定......................................................................................................11 （一）混合所有制改革..............................................................................11 （二）投资效率..........................................................................................13 （三）代理成本..........................................................................................14 二、理论基础......................................................................................................14 （一）信息不对称理论..............................................................................14 （二）委托代理理论..................................................................................15 （三）产权理论..........................................................................................16 （四）投资理论..........................................................................................17 第三章研究设计.................................................................................................18 一、研究假设....................................................................................................18 （一）混合所有制改革与投资效率..........................................................18 （二）混合所有制改革与代理成本..........................................................18 （三）代理成本与投资效率......................................................................19 （四）混合所有制改革、代理成本与投资效率......................................19 二、样本选择与数据来源..................................................................................19 （一）样本选择..........................................................................................19 （二）数据来源..........................................................................................20 三、变量定义与模型构建..................................................................................20 （一）变量定义.......................