Statistical inference of the efficient frontier for dependent asset returns

In the paper we consider the three characteristics of the efficient frontier. These characteristics are estimated by substituting the unknown parameters by the sample counterparts. Assuming that the asset returns follow a stationary Gaussian process it is shown that the estimated characteristics are asymptotically normally distributed. This result is used to determine the joint asymptotic distribution of the estimated portfolio return and the estimated portfolio variance in the case of the expected utility portfolio and the tangency portfolio, respectively.     

目前有效需求不足的实证分析

我国经济运行目前已进入通货紧缩阶段，主要表现为社会总需求小于社会总供给，即有效需求不足。有效需求不足的根本原因是居民收入偏低、农村城镇化进程缓慢、投资主体单一及投资结构不合理，财政政策空间未被充分利用，对外贸易额下降。