定向增发公告效应在股市中的异化现象——关于中国证券市场的实证研究

本文以中国证券市场2006～2008年成功进行定向增发的上市公司为样本,研究了定向增发公告效应在牛市、熊市中的异化现象。研究发现在牛市周期中仅仅公告日当天存在显著的正公告效应,公告日前后都不存在显著的正公告效应;但是在熊市周期中不仅公告日当天存在显著正公告效应,而且从公告日前两天开始一直到公告日后10天都存在显著正公告效应。在不同市场态势下,公告效应与折扣的关系也不相同:在熊市周期中,随着定向增发折扣的增加,公告效应相应减弱,而在牛市周期中公告效应增强。最后,论文给出了基于投资者情绪的理论解释以及相应的启示。     

Do realized betas exhibit up/down market tendencies?

In this paper we employ the STAR (smooth transition autoregressive) model to investigate potential nonlinearities, cyclical behaviour and duration dependence in the realized monthly betas of 39 US industry portfolios. Tests reject linearity for all but eight industries. The estimated nonlinear models suggest that industry betas are characterised by asymmetric cycles, with the speed of transition between the bull and bear market regimes being relatively slow for seven industries. We find duration dependence in industry betas since the probability of transition between regimes does depend on how long the market has been in an up or a down state.     

Non-linear causal linkages of EPU and gold with major cryptocurrencies during bull and bear markets

This paper sets out to explore whether the innovative Economic Policy Uncertainty (EPU) index and the safe haven asset of gold influence returns of high-capitalization cryptocurrencies in a non-linear manner. Estimations take place both concerning flourishing and stressed periods in the digital currency markets. Econometric outcomes reveal that the returns of almost half of the cryptocurrencies investigated are tightly connected to the EPU index in bull markets while even more currencies are linked with the index during bear markets. Similar findings are revealed as concerns gold as it proves to be more influential during bear markets due to its hedging capacities. There is also evidence that causality in variance is significant in all but the higher quantile concerning both EPU and gold estimations in both bull and bear markets.     

“牛市”和“熊市”对信息的不平衡性反应研究

“利好”和“利空”信息对股票市场具有不平衡性的影响 ,研究这一现象对资产定价、投资组合构造及风险头寸确定都有重要作用。而新信息的出现对股票市场的影响应该区分股市所处的位置 ,这一点正是已有的波动性研究所忽视的。中国股票市场总体上不平衡性信息表现与国外不同 ,本文将股票市场波动划分为“牛市”和“熊市”两个阶段 ,采用EGARCH模型实证研究我国股票市场在牛市和熊市阶段对“利好”与“利空”的不平衡性反应特征。然后从投资者预期、结构、心理和交易机制等方面解释产生“强市恒强、弱市恒弱”现象的原因 ,指出进一步研究的方向 ,以期为投资者选择投资策略和政府制订政策提供参考     

牛、熊市状况下人民币汇率与股价关系分析

文章分析了2005年7月人民币汇率改革以后牛熊市下人民币汇率和股票价格的关系,本文发现,在牛市期间,汇率和股票指数在滞后一期上是互为Granger因果关系的,在其余的各滞后期,汇率都是股票指数的Granger原因,而股票指数都不是汇率变动的Granger原因。从两者的互相影响的关系上看,两者在一定程度上互相影响,但是汇率变化对股指变化的影响比股指变化对汇率变化的影响的程度要更深。而在熊市情况下,人民币汇率和股票指数之间不存在协整关系。     

中国股票市场牛熊市运行周期探究

本文运用马尔科夫区制转移模型描述和研究中国股票市场综合指数日收盘价序列的动态轨迹,以此来研究中国股市的牛、熊市周期。实证结果表明,上证和深证综合指数日收盘价在不同的区制状态下均可以表现出较为显著的持续性特征,上证和深证的牛、熊市区间具有明显的协同性。同时发现,中国的经济政策操作与股票市场价格波动及股票市场区制的阶段性转变之间具有明显的相关性。     

Does beta react to market conditions? Estimates of ‘bull’ and ‘bear’ betas using a nonlinear market model with an endogenous threshold parameter

The authors use a logistic smooth transition market (LSTM) model to investigate whether ‘bull’ and ‘bear’ market betas for Australian industry portfolios returns differ. The LSTM model allows the data to determine a threshold parameter that differentiates between ‘bull’ and ‘bear’ states, and it also allows for smooth transition between these two states. Their results indicate that ‘bull’ and ‘bear’ betas are significantly different for most industries, and that up-market risk is not always lower than down-market risk. LSTM models indicate that the transition between ‘bull’ and ‘bear’ states is abrupt, supporting a dual-beta market modelling framework.     

The value of genetic information to livestock buyers: a combined revealed,stated preference approach

DNA profile information has begun appearing in purebred bull auction catalogs; however, the value of this information is as of yet unknown. This study uses data from actual bull sales at a test station and combines it with stated‐preference survey data to determine the value of the DNA profile information. Consistent with previous research, we find that expected progeny differences (EPDs), test performance, and ultrasound information significantly influence bull‐buyers’ willingness‐to‐pay. The newer DNA profile information, however, was unrelated to buyers’ preferences. Methodologically, we find statistically significant differences (but highly correlated willingness‐to‐pay values) across the stated and revealed preference data sources.     

供应链中的“牛鞭效应”分析及弱化措施

本文深入分析了牛鞭效应的危害及成因,探讨了弱化“牛鞭效应”的措施。     

Stock market cycles, financial liberalization and volatility

In this paper we analyze the cycles of the stock markets in four Latin American and two Asian countries, and we compare their characteristics. We divide our sample in two subperiods in order to account for differences induced by the financial liberalization processes of the early 1990s. We find that cycles in emerging countries tend to have shorter duration and larger amplitude and volatility than in developed countries. However, after financial liberalization Latin American stock markets have behaved more similarly to stock markets in developed countries whereas Asian countries have become more dissimilar. Concordance of cycles across markets has increased significantly over time, especially for Latin American countries after liberalization.