湘江流域金属污染的贝叶斯预测实证研究

在中国经济正由“工业主导型”向“服务主导型”转变的背景下，商务服务业的重要性凸显。以商务服务业20家上市公司为研究对象，用ROA和ROE测量其绩效，分析其基本特征、治理结构、股权结构和财务杠杆四个层面共12个变量对绩效的影响。发现商务服务业上市公司2009~2013年绩效未实现明显改善，在低ROA阶段徘徊；各上市公司间绩效存在显著差异；影响因素中，基本特征、股权结构、财务杠杆对绩效的线性回归模型通过了显著性检验。

Forecast Study on Bayesian Forecasting Pollutant Concentration of Heavy-metal Contaminants in XiangJiang Streams

This paper studied the dual risk model with Erlang(n) distributed inter-claim times and exponentially distributed random observations. Under constant dividend barrier strategy and assumption that dividend payments only occur at observation times, integro-differential equations for expected discounted dividend payments until ruin were established. When jump sizes are PH(m) distributed, the analytical solutions for expected discounted dividend payments were given. When jump sizes are exponentially distributed, the specific method to derive the expected discounted dividend payments was investigated. Specially, the explicit solutions when n=1 and numerical example when n=2 were given.