新企业创业导向的测量与功效:基于中国经验的实证研究

当前关于新企业创业导向的维度及其功效还存在较大的分歧。本文从战略过程视角,依据文献分析初步界定了新企业创业导向的5个维度,然后通过访谈调查和探测性检验,将新企业创业导向维度调整为创新性、风险承担性、先动性3个方面,应用并优化了其测量量表。最后通过150份有效样本,对我国新企业创业导向对企业绩效的直接贡献和间接贡献进行了检验。结果表明,创业导向对新企业绩效确实有显著的直接贡献,但间接作用更为明显。     

Improved methods for moment restriction models with data combination and an application to two-sample instrumental variable estimation

Combining-100 information from multiple samples is often needed in biomedical and economic studies, but differences between these samples must be appropriately taken into account in the analysis of the combined data. We study the estimation for moment restriction models with data combined from two samples under an ignorability-type assumption while allowing for different marginal distributions of variables common to both samples. Suppose that an outcome regression (OR) model and a propensity score (PS) model are specified. By leveraging semi-parametric efficiency theory, we derive an augmented inverse probability-weighted (AIPW) estimator that is locally efficient and doubly robust with respect to these models. Furthermore, we develop calibrated regression and likelihood estimators that are not only locally efficient and doubly robust but also intrinsically efficient in achieving smaller variances than the AIPW estimator when the PS model is correctly specified but the OR model may be mispecified. As an important application, we study the two-sample instrumental variable problem and derive the corresponding estimators while allowing for incompatible distributions of variables common to the two samples. Finally, we provide a simulation study and an econometric application on public housing projects to demonstrate the superior performance of our improved estimators. The Canadian Journal of Statistics 48: 259–284; 2020 © 2019 Statistical Society of Canada     

独立定价还是共同定价:新支付工具的定价策略

基于新支付工具发展初期市场特征构建双边市场定价模型，分析共同定价和独立定价策略下企业利润和社会福利最大化新支付工具定价。研究显示：政府较企业对新支付工具制定更低价格水平促使用户支付选择转移，特别是在共同定价策略下会有效提升市场效率，达到社会福利最大；但若政府无法做到共同定价，特别在新支付工具成本优势不明显时，会使支付工具间存在过度补贴而降低社会福利，这时企业利润最大化定价为次优选择。     

润滑油脂中抗氧化添加剂作用机理

本文针对润滑油及润滑脂中主要添加剂──抗氧化添加剂的作用机理，从化学反应角度进行理论探讨，并进行了实例分析．     

虚拟逻辑分析仪的开发

阐述了利用虚拟仪器概念研制的逻辑分析仪原理及其在设计中为提高采样速率,促进仪器小型化、增加电路可靠性、提供友善的用户界面等方面所做的具体工作和采取的具体措施。本文所述的虚拟仪器原理及其设计方法,在本世纪90年代的仪器开发中具有重要意义。     

二级反应──乙酸乙酯的皂化实验方法的探讨

本文对“二级反应──乙酸乙酯的皂化”这一物理化学实验的实验操作和仪器作了适当的改进，取得了较为理想的效果。     

高温超导薄膜微波表面特性的研究

研究和设计了“终端反射式带状线谐振器”测试系统,配合测量数据处理软件包,对高温超导薄膜的微波表面特性进行了测试分析。     

Estimation of a standard measuring error by repeated measurements and sortings

A sorting-and-measuring machine (SMM) measures and sorts (classifies) on-line produced items into several groups according to their size. The measuring devices of the SMM perceive the actual item size with a random error ε and classify the item as being smaller than b iff z+ε<b. Here ε is a normal zero-mean r.v. with unknown standard deviation σ which is the main parameter characterizing the precision and technical condition of an SMM. The paper gives the following method of estimating σ. N₀ items are measured and N₁ of them are recognized by the SMM as belonging to the group a<z≤b. These N₁ items are sorted again and N₂ of them return to this group, these are sorted again, and so on. The estimation of σ is based on the statistics N_m/N_n. Moments of the ratio statistics N_m/N_n and their distributional properties are investigated. It turns out that the expected value of N_m/N_n depends almost linearly on σ which allows us to construct ‘almost’ unbiased estimators of type $\text{σ}\text{?}{}_{\mathrm{mn}}\text{=A}\textcolor{red}{}\text{N}{}_{\mathrm{m}}\text{/N}{}_{\mathrm{n}}\text{+B}$ with good propert including robustness with respect to the distribution of item size. Convex combinations of $\text{σ}\text{?}{}_{\mathrm{mn}}$ statistics are considered to obtain an estimator with minimal variance.     

个体异质性与环境公共物品的私人有效供给

解决累积性环境恶化问题亟需所有个人与组织转变行为方式,为实现环境公共物品的有效供给而共同努力。基于个体异质性,选取最重要的异质性维度——偏好异质性和成本异质性,分析在单维和多维场景下,个体有效提供环境公共物品的均衡条件,以及政府环境政策工具的实施效率。研究结果表明:只存在个体偏好异质性时,潜在的大集团无法实现环境公共物品的有效供给,强制控制方法通过设立企业必须遵守的排污限制和技术标准等,能够提高环境公共物品的供给效率;而同时存在个体偏好异质性和成本异质性时,市场化方法能够发挥其资源有效配置的基础性作用,通过规避强制标准检测、执行的困难和政策后果的不确定性,提供比后者更高水平的环境公共物品。结合研究结论,认为应强化环境信息公开,加大环保法规标准执行力度,明晰环境治理责任主体,通过利益杠杆调动公众积极性。     

Problem characteristics, decision processes and evaluation activity: a preliminary study of mental health center directors

This article reports on the results of a preliminary study on the characteristics of problems and problem solving in mental health centers. The major findings were that directors were generally quite satisfied both with the available level of information intended to help them make decisions, and with their ability to make good, even optimal, decisions. Much of this confidence resulted from the use of assumptions about the problems which reduced the need for empirical information. The problem solving process was highly dynamic and interactive, with changes over time in the characteristics of problems, constraints and alternative solutions. The directors played an active role in attempting to foster and influence the direction of many of these instabilities. Some implications for evaluation and research are discussed.