中国股市收益和交易量动态引导关系的实证分析

实证检验沪深A、B股市场日收益和交易量之间的线性和非线性Granger因果关系。由于序列存在非线性结构可能使检验发现的仅是一种伪Granger因果。我们着重考察运用APGARCH模型过滤后股市收益和交易量之间的线性和非线性Granger因果。研究表明,上证A、B和深证A股市场收益和交易量之间互为线性Granger因果,深证B股仅存在从收益到交易量的线性Granger因果;上证A股市场交易量是收益的非线性Granger引导,深证B股市场收益和交易量之间互为非线性Granger引导。研究发现沪深A、B股市场收益和交易量之间具有相互的动态引导关系。     

上海期货市场收益波动性的实证分析——基于EGARCH模型的应用

本文利用EGARCH（1，1）模型对上海期货市场的三个交易品种天然橡胶、铜、铝的收益率波动进行估计，考察了交易量、持仓量和收益波动的动态关系，然后再考虑滞后一期交易量和持仓量对收益波动的影响。实证结果显示：上海期货市场不存在杆杠效应，同时收益波动具有一定的持久性和聚集性。橡胶和铝不管是同期还是滞后一期的交易量和持仓量对收益波动的影响都为正。铜交易量和收益率波动没有显著的关系，但是同期和滞后一期持仓量对收益率波动有显著的负向影响。     

我国股市波动非对称性和混合分布假定的经验分析

混合分布假定(MDH)用信息流的自相关结构解释收益波动的GARCH效应和持续性。本文先运用EGARCH—GED模型考察沪深A、B股市场的波动非对称性,发现A股市场波动显著非对称、B股市场“杠杆效应”不显著。然后,我们根据“杠杆效应”的显著与否,把同期交易量作为信息替代指标分别引入EGARCH—GED和GARCH—GED模型的条件方差方程,实证检验混合分布假定。最后,我们比较预期和未预期交易量对条件方差的解释力。研究表明：在B股和上证A股市场上,同期交易量对收益波动的GARCH效应和持续性有显著的解释力;同期交易量不能作为市场信息的完全替代指标;未预期交易量对收益波动有显著的解释力、比预期交易量的解释力强。     

广东省香蕉产业对农户收入贡献研究

广东省是我国香蕉最大的主产地,为研究广东省香蕉生产对农户收入贡献从而更好地促进更好地促进香蕉产业的发展,本研究基于分层重点抽样的方法,对广东省重点村镇的香蕉种植户进行了一对一访谈,以探究香蕉生产对当地的经济贡献。研究发现:广东省香蕉生产对当地种植户经济贡献大,但不同产区之间香蕉种植户之间存在差异。对种植户而言,香蕉生产带来的现金收益平均每亩为1,133.58元。而加总生产环节用工报酬、农资使用贡献和采后劳务费用后,香蕉平均每亩生产对当地的直接总体贡献为3,525.27元。     

燃料油期货市场收益波动性实证分析

本文采用GARCH和EGARCH波动率模型分析了燃料油市场中,交易量、持仓量与波动率的关系,描述了该市场的微观结构。发现交易量与波动率成正向关系,而持仓量与波动率成负向的关系。此外,非预期的交易量和持仓量没有比预期值更显著的作用,说明收益波动性对信息的依赖不是很大。EGARCH模型比GARCH模型拟和效果要好,更能反映出波动率的持续性。但模型估计后杠杆效应不明显或者不存在,这反映了期货市场的零和博弈特征。     

中国农村小额信贷市场中政府扶持行为的博弈分析

农村小额贷款已成为我国扶贫工作的重要组成部分,但是小额信贷风险较大、收益较低的特点使得小额信贷的发展还需依仗政府的扶持。本文通过博弈论的方法,分析政府在扶持小额贷款金融机构时出现的四种均衡结果,即小额信贷市场部分成功的混同均衡、市场完全成功的分离均衡、市场完全失败的混同均衡以及市场接近失败的混合策略均衡,为政府如何在信息不对称情况下实施有效的扶持措施提供了一定的指导意义。     

中国市场中股票间领先-滞后关系的规模与交易量效应

本文检验了中国市场中股票间收益率领先 -滞后关系的规模效应与交易量效应。结果表明 ,控制了交易量后 ,基于规模领先 -滞后关系整体表现不明显。当市场上升时 ,小市值股票领先大市值股票 ;而当市场下跌时 ,大市值股票领先小市值股票。控制了规模后 ,基于交易量的领先-滞后关系十分显著 ,高交易量的股票收益对低交易量股票收益有较强的预测力。但这种关系主要表现在市场上升的状态中 ,市场下跌时领先 -滞后关系不明显。中国市场股票信息的来源、投资者结构及其信息扩散模式与成熟市场的差异决定了股票间领先 -滞后关系的特征。     

境外上市企业回归发行A股的公告效应研究

文章采用事件研究法对境外上市企业回归发行A股的公告效应进行研究,样本为1993-2008年21家先在香港市场发行H股,后到内地市场发行A股的上市公司。实证研究结果表明：以A股上市日为事件日,在（-40,＋40）的事件窗口内．境外股票价格的平均超额收益率和累计超额收益率均未出现显著变化,但事件日后境外股票的波动和交易量都比事件日前有所增长。     

上证综合指数的星期效应检验

对1992年5月21日至2002年6月21日上证综合指数星期效应的检验，发现周五的平均收益最高，周四次之，周一，周二的平均收益均为负，周二平均收益最低；对10％涨跌停板制度前后两个时期分别进行考察的结果，发现前一时期星期效应的模式和整体样本一致，而后一时期却是周三收益次高，周一平均收益最低。     

中国国有企业效率研究——基于全要素生产率增长及分解因素的分析

本文实证研究的结果发现,中国现阶段分行业国有企业的全要素生产率显著地高于外资企业和行业平均,这与先前文献所得到的国有企业效率低下的结论完全相反,对固有观念提出了挑战并为国有企业的效率及改革成就提供了证明。通过采用数据包络分析的Malmquist指数方法,对2003~2008年行业加总的国有企业实证核算了全要素生产率和分解,并与外资企业和行业平均进行比较,结果发现国有企业的全要素生产率具有绝对优势,但主要依赖于技术进步的贡献;国有企业的低效率主要体现在技术效率和规模效率较低。故而政策上应该进一步深化改革,完善国有企业的内部管理和激励,进一步提高技术效率。     

投资者面临泡沫的理性行为:抛售、旁观还是骑乘?

关于投资者面临泡沫时的行为,学术界存在截然不同的三种观点:抛售、旁观和骑乘。本文构建了一个仅需基本信息的、适用于一般投资者的泡沫识别模型,以1996年5月至2010年12月的数据为样本识别泡沫,在此基础上分析泡沫期之后的崩溃风险,并测算投资于泡沫期之后的超额收益,探寻当期识别到泡沫与下一期标准化的超额收益之间的关系。结果表明,崩溃与泡沫没有必然联系,投资者面临具有极端收益的泡沫时的理性行为是骑乘泡沫。     

OWGA算子在乡村干部业绩优劣评价排序中的应用

有序加权几何平均（OWGA）算子是一种能有效地集结数据信息的方法。在多人决策中有时需要不同专家对决策方案进行两两比较给出互反判断矩阵的偏好信息,为了反映群体的共同偏好,可以利用OWGA算子对互反判断矩阵进行集结处理得到组合判断矩阵。文章利用这一算子建立村民评委对村干部年终业绩优劣评价排序的数学模型,最后进行了实例分析。     

Adverse Selection in Private Annuity Markets and the Role of Mandatory Social Annuitization

We study the effects on the macroeconomic equilibrium, the wealth distribution, and welfare of adverse selection in private annuity markets in a closed economy inhabited by overlapping generations of heterogeneous agents who are distinguished by their health status. If an agent’s health type is private information there will be a pooling equilibrium in the private annuity market. We also study the implications for the macro-economy and welfare of a social security system with mandatory contributions that are constant across health types. These social annuities are immune to adverse selection and therefore offer a higher rate of return than private annuities do. However, they have a negative effect on the steady-state capital intensity and welfare. The positive effect of a fair pooled rate of return on a fixed part of savings and a higher return on capital in equilibrium is outweighed by the negative consequences of increased adverse selection in the private annuity market and a lower wage rate.     

Nonlinear and time-varying risk premia

Facing the puzzling risk-return trade-off, this paper proposes a new model for risk premia to capture nonlinear and time-varying features under the influence of trading volume. Using high-frequency data for the US stock market in Wharton Research Data Services' Trade and Quote database, our empirical findings suggest a significant nonlinear and time-varying contemporary relationship between return and realized volatility, ranging from positive to negative with an up-down-up pattern, summarized as follows. First, the contemporary relationship is positive on inactive trading days when the trading volume is smaller than usual, in which case traders may face no new information or event uncertainty. Second, the relationship is significantly negative when the trading volume is large on active trading days, in which case traders may be overconfident and behave in a risk-seeking fashion. Third, the risk premium tends toward zero during extremely abnormal trading days. Finally, low and high levels of trading volume have asymmetrical influences on risk premia, with a larger absolute value of risk premia for high levels of trading volume. Furthermore, the nonlinear changing autocorrelation of returns is insignificant from zero on normal trading days and most likely different from zero on abnormal trading days. These results provide explanations for the conflicts between financial theoretic and empirical studies.     

The Dutch Grey Market

When-issued trading concerns transactions in securities that have not yet been issued. This paper investigates the Dutch “grey market” for when-issued shares prior to stock splits, using a unique hand-collected data set. Market makers are more likely to set up a when-issued market when the underlying firm is larger, the relative trading volume of the stock is higher, and the stock return is less volatile. The when-issued securities trade at a small premium over the regular shares during the weeks prior to the stock split, but this when-issued premium disappears in the last days of trading.     

The winner–loser effect in Japanese stock returns

This study examines the winner–loser effect using stocks listed on the Tokyo Stock Exchange (TSE) from 1975 to 1997. We uncover significant return reversals dominating the Japanese markets, especially over shorter periods such as 1 month. No momentum effect is observed, however. The 1-month return reversal remains significant even after adjusting for firm characteristics or risk. While the 1-month return reversal is not related to industry classification, it is partially a result of higher future returns to loser stocks with low trading volume. Our results show that investor overreaction may be a possible explanation for the 1-month return reversal in Japan.     

The Relation between Aggregate Earnings and Security Returns over Long Intervals*

This paper provides a theoretical explanation and consistent empirical evidence for the increase in the contemporaneous correlation between returns and aggregate earnings as the return interval is lengthened. Consistent with intuition and with Easton, Harris, and Ohlson 1992, the analysis shows that aggregation over time renders the lag in accounting recognition relatively less important and thus improves the returns‐earnings R². Interestingly, the analysis also reveals that aggregating earnings over longer periods increases the positive covariance between aggregate earnings and the accounting lag, which may further increase the R². This positive covariance can lead to an earnings coefficient greater than one over some range of aggregation, which is consistent with the findings of Easton et al. that over the 10‐year interval the returns‐earnings regression slope coefficient is greater than one (1.7). The empirical results highlight the fact that the slope coefficient, which is greater than one and increasing with the interval, accounts for much of the increment to the returns‐earnings R². In fact, constraining the slope coefficient to be one results in an R² of 11 percent for the 10‐year interval, which is considerably lower than the R² of 47 percent when the regression is unconstrained. Hence, the positive covariance between current earnings and the accounting lag, rather than the diminishing effect of the accounting lag, appears to be the dominant explanation for the observed high R² over long intervals.     

The Rising Supply of College Graduates and Declining Returns for Young Cohort: The Case of Korea

Abstract

This study analysed the effect of an increase in the supply of youth college graduates, in terms of the return on education. The rate of return on education in Korea substantially dropped from 1983 to 1994. Since then, however, the declining trend of the rate of return on education stopped and turned upward. The rate of return has declined especially for college graduates, and such a decline has been most prominent for young cohorts, among college graduates, since 1987. The observed trend of the rate of return appears to be related to the sharp increase of labour supply of college graduates since the mid 1980s.

The elasticity of substitution between education levels and age groups was estimated in this study, using a generalized demand-supply model. The effects of relative supply of college graduates (as a whole and by age) on the relative wages of college graduates by age were analysed under the assumption of constant skill-biased technological change. As it turned out, the relative college graduates’ labour supply of each age group had large bearings upon relative wages of each corresponding group, while the relative labour supply of all college graduates did not. It implies that labour is an imperfect substitute, not only between education levels but also between age groups.

Thus, as youth college graduates’ supply increases, there needs to be a corresponding demand increase for them, to avoid the drop in the wage or employment level for them. Therefore, to tackle with the issues of youth labour market, such as youth unemployment, separate policies targeting the youth group are called for.     

Going Home: Evacuation-Migration Decisions of Hurricane Katrina Survivors

In the wake of Hurricane Katrina, many evacuees from the Gulf region began the difficult process of deciding whether to rebuild or restart elsewhere. We examine pre-Katrina Gulf residents' decision to return to the postdisaster Gulf region—which we call the “return migration” decision. We estimate two separate return migration models, first using data from a mail survey of individuals in the affected region and then focusing on self-administered questionnaires of evacuees in Houston. Our results indicate that return migration can be affected by household income; age; education level; and employment, marital, and home ownership status, but the results depend on the population under consideration. We find no effect of “connection to place” on the return migration decision. Although the effect of income is relatively small within subsamples, we find a much higher proportion of middle income households planning to return than lower income households when comparing across the subsamples. In addition, the real wage differential between home and host region influences the likelihood of return. Larger implicit costs, in terms of foregone wages for returning, induce a lower likelihood of return. Exploiting this difference at the individual level, we are able to produce estimates of willingness to pay (WTP) to return home. Average WTP to return home for a sample of relatively poor households is estimated at $1.94 per hour or $3954 per year.     

考虑有限关注的多个信息交易者竞争交易分析

文章假设在一个具有唯一风险资产的金融市场中，存在多个风险中性的信息交易者、很多噪音交易者、风险中性的做市商三类交易者，其中信息交易者是有限关注的，他们通过权衡关注和竞争两种因素选择交易量。文章首先建立了信息交易者具有不同关注度的一般模型，然后建立了具有相同关注度的模型，通过求解唯一线性均衡，推导它的均衡特征，得出结论：信息交易者的交易强度、期望收益随着其他信息交易者关注度和信息交易者数量的增大而降低，随着自身的关注度的增大而增大；信息交易者数量较少时，期望收益随着信息交易者关注度的增大而增大；而信息交易者数量较多时，期望收益随着信息交易者关注度的增大起初快速增大，然后缓慢降低。