我国上市公司股利分配政策的同群效应研究

公司股利分配政策深受监管机构和投资者长期关注,对于公司内部治理和价值提升具有重要影响。在2023年沪深交易所出台《上市公司现金分红指引》的大背景下,对股利分配政策的同群效应进行研究具有现实意义。本文使用工具变量两阶段Probit模型,实证检验了沪深A股市场股利分配政策同群效应的表现及异质性。研究发现,我国上市公司在制定和实施股利分配政策时存在显著的同群效应,这种同群效应主要表现为行业内小市值公司对大市值龙头公司的跟随效应。股利分配政策的同群效应具有“非对称性”:行业内大市值公司会按照行业惯例在非现金股利分配方面表现出同群效应,而行业内小市值公司更倾向于跟随行业标准在现金股利分配方面表现出显著的同群效应。公司调升和调降股息率对于行业内其他公司股利分配政策的同群效应具有异质性。本文进一步从信息优势和行业竞争两大假说的基本假设出发,对同群效应的成因进行讨论。本文的研究对于证券监管部门规范和引导上市公司制定股利分配政策具有重要的政策含义。

Atmospheric Environmental Quality Prediction Based on Support Vector Machine

The economic development bring serious environmental problems to China, the quality of atmospheric environment has an important bearing on the forecast. Be aimed at the complexity and non-linear of the quality of atmospheric environment, chaos theory has been put forward which takes full advantage of using date information. Based on the reconstruction of time-series phase space of the quality of atmospheric environment with the use of least squares support vector machine theory, the atmospheric environment prediction model was built up, and 25 years of historical data viewed as the raw data of the quality of the environment in Benxi City, giving a practical example, it shows that the results forecasted by the least squares support vector machine and the actual results match the better the forecast accuracy also meet the engineering application.