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单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part,1,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part 1,Part 2,Part 3,Part 4,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part,2,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part 1,Part 2,Part 3,Part 4,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part,3,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part 1,Part 2,Part 3,Part 4,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part,4,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part 1,Part 2,Part 3,Part 4,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,Part,5,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,我国股票市场有效性分析,组员:胡畔、闫晓虹、李欢、李燕楠、王晓蕾,2025/12/27 周六,1,目录,P,art1,有效市场的概念及层次,P,art2,市场有效性的分析步骤,P,art3,实证分析,P,art4,结论,2025/12/27 周六,2,有效市场及其层次,2025/12/27 周六,3,有效市场及其层次,有效市场:如果一个市场的证券价格总是能够,“,充分反映,”,所有可以得到的信息,则该市场为,“,有效的,”,。,假设:(1)整个市场没有摩擦,即不存在交易成本和税收;所有资产完全可分割、可交易,没有限制性规定;,(2)整个市场充分竞争,所有市场参与者都是价格的接受者;,(3)信息成本为零;,(4)所有市场参与者同时接受信息,所有市场参与者都是理性的,并且追求效用最大化。,2025/12/27 周六,4,有效市场及其层次,历史信息,公,开,信,息,幕,内,息,消,历,史,信,息,弱 式,有,效,半,强,式,有,效,强,式,有,效,2025/12/27 周六,5,市场有效性的分析框架,2025/12/27 周六,6,市场有效性分析框架,游程检验,序列相关检验,根检验,事件研究法,针对,专业机构,内幕人士,弱式有效市场分析,半强式有效市场分析,强式有效市场分析,2025/12/27 周六,7,实证分析,2025/12/27 周六,8,实证分析,(,弱式有效性检验,),方法一:游程检验,游程:某种符号连续相同的段,在检验股票市场的有效性中,可以理解为股票价格变化保持相同符号的一个序列。,实际中,股票价格变化有三种形式,股票价格上升、股票价格不变、股票价格下降,相应地,就有正游程、零游程、负游程三种形式,在本应用中只有正游程和负游程两种情况。,正游程表示的是当期股票价格比上一期股票价格高的序列,游程的长度是股票价格保持这种趋势的时段长度,比如一个长度为 K的正游程表示的是,股票价格正的价格变化连续出现 K 次,随后股票价格不变或是股票价格下降。,2025/12/27 周六,9,实证分析,(,弱式有效性检验,),步骤一:确定游程数的计算,步骤二:构造统计量,步骤三:数据整理,步骤四:运用EXCEL进行数据分析,2025/12/27 周六,10,实证分析,(,弱式有效性检验,),首先定义价格转折示性数It:当P,t,P,t-1,时,I,t,=1,否则I,t,=0。否则,I,t,=0。令X,t,=I,t,(1-I,t-1,)+I,t-1,(I,t,-1),由此式可知当I,t,=I,t-1,时,X,t,=0,即此时计一次游程数,从而可以统计其累计游程数m。,其次构造统计量Z:如果股票价格符合随机游走,且样本容量足够大时,总游程数m 服从正态分布,根据正态分布的定义及游程检验的计算公式,我们可以构造标准正态分布统计量,Z=m-E(m)/,。其中 E(m)为总游程数 m 的期望值,为总游程数 m 的标 准差。,原假设,:股票价格变化是,随机,的;,备择假设,:股票价格不是随机的,而是,具有某种变化趋势,。根据游程个数是否落在接受区域将原假设及备择假设变换为:,原假设,:,游程数 x,满足条件,m-1.96xm+1.96,备择假设,:,游程数 x,不满足条件,m-1.96xm+1.96,2025/12/27 周六,11,实证分析,(,弱式有效性检验,),excel数据分析结果,表,1,:沪深两市游程检验各指标值结果表,上证综合指数,深圳成份指数,样本区间,1990.12.19-2015.05.22,1991.04.03-2015.05.22,样本数,5974,5884,n1,3147,2926,n2,2827,2958,游程数,m,2842,2851,游程数期望值,E,(,m,),2979.43,2942.91,游程数方差,1484.69,1470.66,游程数的根方差,38.53,38.35,m-1.96*,2766.48,2775.83,m+1.96*,2917.52,2926.17,数据来源:网易财经,2025/12/27 周六,12,实证分析,(,弱式有效性检验,),方法二:序列相关检验,序列相关检验的依据:在一个弱式有效市场上,股票价格序列具有随机游走特性,股票收益率序列之间是不相关的,股票价格的收益率围绕其均值上下波动,收益率序列是平稳的,不存在相关性或相关系数接近于零。,序列相关性的相关程度,我们可以用相关系数来度量:,=cov(R,t,R,t-1,)/var(R,t,),运用Eviews6.0进行数据处理,输出结果如下:,2025/12/27 周六,13,实证分析,(,弱式有效性检验,),上证综合指数日收益率序列的Q统计量值,数据来源:网易财经,2014.07.01-2015-05-22,1991.04.03-2015.05.22,1991.04.03-2010.10.29,表2,表1,表3,2025/12/27 周六,14,实证分析,(,弱式有效性检验,),深证成份指数日收益率序列的Q统计量值,1992.12.22-2015.05.22,1992.12.22-2010.10.29,2013.02.01-2015.05.22,数据来源:网易财经,表1,表2,表3,2025/12/27 周六,15,结果显示:沪深两市所有可得数据显示其Prob值均为0,即存在序列相关,说明我国股市并未达到弱式有效;调整数据样本,分别选取沪市1991.04.03-2010.10.29和深市1992.12.22-2010.10.29的数据可以发现其Prob值发生了变化但仍然小于5%的显著水平;进一步调整样本数据,分别选取沪市2014.07.01-2015-05-22、深市2013.02.01-2015.05.22数据,此时输出结果中10阶Prob值也明显大于显著性水平5%,说明在此阶段我国股市已经,实现了完全弱有效。,实证分析,(,弱式有效性检验,),此处可能需要进一步的思考和讨论,同时欢迎大家的解答!,2025/12/27 周六,16,实证分析,(,弱式有效性检验,),方法三:单位根检验,单位根检验也是用来检验序列的平稳性,我们根据趋势图的平稳与否来对是否需要截距项进行判断。,沪,市,深市,由图,4.1,和图,4.2,可以初步判断股价时间序列是,不平稳,的,在使用,ADF,检验,时,使用带截距项和趋势项的模型,。,2025/12/27 周六,17,日收益率序列的序列相关检验的 T 统计量值,显著性水平,SCI准则下的T统计量,沪市,P,沪市,D(P),深市,p,深 市,D,(,p,),-2.05232,-50.496,-3.56473,-71.9991,1%level,-5.12488,-5.12488,-5.52186,-5.52186,5%level,-3.93336,-3.93336,-4.10783,-4.10783,10%level,-3.42003,-3.42003,-3.51504,-3.51504,实证分析,(,弱式有效性检验,),结果表明:对于沪深股市的股价序列,具有单位根,是非平稳的,而一阶差分 D(P)序列不具有单位根,为平稳时间序列,说明根据 SIC准则,沪深股市的股票价格均符合,“,随机游走,”,,,市场具有弱式有效性。,2025/12/27 周六,18,实证分析,(,半强式有效性检验,),基于超额收益率视角的研究,基于股价的信息含量视角的研究,事,件,研,究,法,事,件,研,究,法,公司年报,分红派息,股票分割,资产重组,新股发行,公司兼并,通货膨胀,新股发行后,超额收益率变化来说明新股的短期价格行为,进而说明我国,股票市场的有效性,新股发行后,发行价是否充分反映了发行公司基本面的信息以及外部市场环境方面的信息,2025/12/27 周六,19,实证分析,(,半强式有效性检验,),样本介绍:,2010,年,1,月至,2015,年,5,月共发行新股(,A,股),623,支,根据新股市盈率从高到低排列,分别选取市盈率前,20,支股为研究对象 (,2015,年,4,支,,2014,年,4,支,,2012,年,4,支,,2011,年,4,支,,2010,年,4,支)。以申购日为事件日,选取上市日起的,10,个交易日内日收盘价为样本数据,选择事件日后,10,个交易日作为事件窗,主要是基于市场对于信息的消化需要一定的时间,另外也可以在一定程度上排除其他事件对报酬率的影响。,从新股二级市场价格的信息含量角度来分析时,选用的个股与超额收益率研究角度的样本相同,为,20,支个股,选用数据有市盈率、发行总数、中签率、发行日至上市日的时间间隔。,基于超额收益率视角的研究,2025/12/27 周六,20,实证分析,(,半强式有效性检验,),证券简称,发行日,上市日,发行量,(,万股,),网上发行量,(,万股,),发行价,(,元,),市盈率,中签率,1,星河生物,2010/11/29,2010/12/9,1,700,1,360,36,138.46,0.40%,2,新研股份,2010/12/27,2011/1/7,1,060,850,69.98,150.81,1.28%,3,沃森生物,2010/11/1,2010/11/12,2,500,2,000,95,133.8,1.48%,4,汤臣倍健,2010/12/6,2010/12/15,1,368,1,098,110,115.29,0.85%,5,雷曼光电,2011/1/4,2011/1/13,1,680,1,355,38,131.49,0.64%,6,先锋新材,2011/1/4,2011/1/13,2,000,1,600,26,123.81,0.69%,7,铁汉生态,2011/3/21,2011/3/29,1,550,1,240,67.58,110.06,0.94%,8,国电清新,2011/4/11,2011/4/22,3,800,3,040,45,104.65,2.10%,9,华录百纳,2012/2/1,2012/2/9,1,500,1,200,45,82.45,4.61%,10,天山生物,2012/4/17,2012/4/25,2,273,1,821,13,56.52,0.91%,11,西部证券,2012/4/23,2012/5/3,20,000,16,000,8.7,48.32,1.27%,12,煌上煌,2012/8/28,2012/9/5,3,098,2,168,30,47.61,2.99%,13,纽威股份,2014/1/9,2014/1/17,8,250,4,125,17.66,46.46,1.77%,14,全通教育,2014/1/13,2014/1/21,1,630,978,30.31,51.36,1.68%,15,天保重装,2014/1/10,2014/1/21,2,570,1,998,12,41.38,1.23%,16,恒华科技,2014/1/15,2014/1/23,1,208,604,43.21,42.15,2.05%,17,昆仑万维,2015/1/13,2015/1/21,7,000,6,300,20.3,22.98,0.77%,18,东方证券,2015/3/11,2015/3/23,100,000,70,000,10.03,22.98,1.62%,19,龙津药业,2015/3/12,2015/3/24,1,675,1,508,21.21,22.98,0.64%,20,蓝思科技,2015/3/10,2015/3/18,6,736,6,062,22.99,22.98,0.66%,数,据,来,源,.,网,易,财,经,2025/12/27 周六,21,实证分析,(,半强式有效性检验,),从,20,支样本股的累计超额报酬图来看,上市日收盘价高于新股发行价,上市首日的超额收益高,从第,2,个交易日开始,累计超额收益率呈明显的下降趋势,在第,6个交易日出现上升,而后又呈现下降态势。说明在上市前获知新股发行这一利好消息的投资者对新信息过度反应,造成高的超额收益,在上市第,2,个交易日起,市场消化信息,对前期的过度反应进行相应的调整,使股票价格向其内在价值靠近,市场对信息的,过度反应,说明,我国股市尚未进入半强式,。,2025/12/27 周六,22,基于上市首日的超额收益率变化情况从时间层面进行分析,发现从,2010,年至,2015,年新股发行中,新股发行上市首日的超额收益率在,2011,年之后呈现明显的下降,说明我国股市对新股发行利好消息的过度反应程度下降,,有效性水平提高,。从对过度反应的调整速度来看,,2010,年至,2015,年新股发行中,从第二个交易日起超额收益率明显下降,且超额收益率在零值附近上下波动,说明市场对前期过度反应的调整速度快。,实证分析,(,半强式有效性检验,),2025/12/27 周六,23,实证分析,(,半强式有效性检验,),2025/12/27 周六,24,(二),基于股价的信息含量视角的研究,模型如下:,AR,i,t,=P,i,t,/P,i,t-1,-P,m,t,/P,m,t-1,其中,,P,i,t,是第,i,支股票第,t,个交易日的收盘价,,P,m,t,是第,t,个交易日综合股价指数,,AR,i,t,表示第,t,个交易日第,i,支股票的超额报酬率,P,i,0,是新股发行价,,P,m,o,是发行日综合股价指数,为了研究方便,本文直接采用上市交易日的前一个交易日的综合股价指数。,假定总样本为,N,根据个股的超额收益,可以计算平均超额收益,:,实证分析,(,半强式有效性检验,),计算出,20,支样本股票的平均超额收益率,再据此计算出累计超额收益,CAAR,:,2025/12/27 周六,25,序号,股票,简称,第,i,个交易日超额报酬率,1,2,3,4,5,6,7,8,9,10,1,星河生物,0.324651,0.080542,-0.00231,-0.0205,0.003817,0.007604,0.093529,0.029054,0.097773,0.027517,2,新研股份,0.495991,0.026453,-0.0428,-0.04918,-0.05871,-0.02387,-0.02618,-0.0283,0.006217,-0.0583,3,沃森生物,0.479828,0.002398,-0.02438,0.050101,0.04085,-0.02073,-0.0638,-0.01038,-0.00177,0.006101,4,汤臣倍健,0.339879,-0.03054,0.056749,0.052688,0.00719,0.026692,-0.0376,-0.00207,-0.00622,0.029345,5,雷曼光电,1.848019,-0.02634,-0.02147,-0.03778,-0.00352,0.000232,-0.01165,0.013911,-0.02412,0.194752,6,光锋新材,0.111604,-0.07179,-0.03099,0.010193,-0.01678,-0.04194,-0.02556,-0.00854,-0.00238,-0.00902,7,铁汉光泰,0.16676,-0.07416,0.065814,-0.46257,-0.08644,0.055382,0.075515,0.039001,-0.06052,0.978754,8,国电清新,-0.07583,-0.0024,0.01315,-0.05937,-0.04177,-0.00234,0.009761,0.01003,-0.00267,0,9,华录百纳,0.224514,0.000104,0.00305,-0.0261,0.012178,0.004205,0.055627,-0.02132,-0.01015,-0.02422,10,天山生物,0.183163,-0.0174,0.089873,-0.02507,-0.03333,-0.00854,-0.04648,0.044852,0.019939,-0.00317,11,西部证券,0.6625,0.008569,0.029459,-0.0179,-0.00034,0.049824,0.007099,0.041086,0.074586,0.006478,12,煌上煌,0.0881829,0.002867559,-0.04098084,0.012087185,-0.018769817,0.02522747,-0.011164,0.001875028,-0.01134,0.0086921,13,纽威股份,0.444146,-0.09301,-0.04978,-0.02117,-0.00448,0.038763,-0.04757,0.009621,-0.07689,-0.04314,14,全通教育,0.436827,0.082502,-0.0206,0.084434,0.019657,0.060492,-0.08234,0.02753,-0.03396,0.086493,15,天保重装,0.426600012,0.082410151,0.079401918,0.042206251,-0.095446063,-0.0415557,0.00481167,0.090812075,-0.02079,0.0863814,16,恒华科技,0.431171858,0.024178476,-0.09293227,-0.022550468,-0.038237376,-0.056505366,0.01062158,0.041989734,0.0224474,0.0717842,17,昆仑万维,0.427125513,0.087439309,0.126961099,0.075044901,0.097738398,0.107036842,0.11161686,0.118010743,0.0903834,0.0681767,18,东方证券,0.420216271,0.098725088,0.108437132,0.094334089,0.097451684,0.022857882,0.03186329,0.014258422,0.0648854,0.0901884,19,龙津药业,0.438888942,0.108180212,0.094192137,0.097691061,0.074258083,0.110167686,0.08337367,0.095916212,0.0899946,0.0302248,20,蓝思科技,0.418923,0.09953,0.086258,0.064017,0.072025,0.088574,0.13903,0.086092,0.114301,0.080517,实证分析,(,半强式有效性检验,),2025/12/27 周六,26,基于股价信息视角的研究,实证分析,(,半强式有效性检验,),2025/12/27 周六,27,实证分析,(,半强式有效性检验,),运用,EVIEWS6.0,进行回归,结果如下,:,2025/12/27 周六,28,结 论,2025/12/27 周六,29,避开行为,金融学理论,结 论,1,2,3,4,SUGGESTION,回避行为金融学理论,结 论,经过检验:我国股票市场已经实现了弱有效,短期尚未实现半强式有效,中期,实现了半强式有效,投资者理性,心理账户,保守主义,经验判断,噪声交易者,冒险心理,2025/12/27 周六,30,谢谢!,欢迎大家批评指正!,2025/12/27 周六,31,
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