投资者情绪与股票收益间的关系研究

在构建投资者情绪指数的基础上,分别采用线性和非线性Granger因果检验对投资者情绪与股票收益间的关系进行研究,并进一步研究不同市态下两者间的关系.研究结果表明,在全样本下,投资者情绪与股票收益间存在单向的线性因果关系和显著的双向非线性因果关系,表明使用非线性Granger因果检验的方法,能够更全面地了解中国投资者情绪与股票收益间的关系;在牛市和熊市状态下,投资者情绪与股票收益间的非线性因果关系并不一致,这与中国股票市场的实际情况是相符合的,说明中国股票市场中存在大量的非理性情绪.

Research on the Bottleneck Delay of Internet IP-Level Topology

With IP level data collected from CAIDA, the characteristic of bottleneck in Internet was analysed. First, a statistical analysis about critical delay of network paths was made, and it found that the bottleneck delay appeared in more than 80% network paths. And then a quantitative analysis on the bottleneck delay suggested that the bottleneck made the similar network diameter’s network delay distinct. Furthermore, an analysis on IP addresses of the network delay and bottleneck delay from the degree of the geography location was performed, it appeared that there was a big difference between network delay and bottleneck delay. Finally a research on the causing of the bottleneck has been made, which indicated that propagation delay was the main factor of the bottleneck delay for long distance, whereas the queue delay is the main factor for a short range.