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791.
792.
An ARIMA(p,1,0) signal disturbed by MA(q) noise is an ARIMA(p,1, p+q+1) process restricted by nonlinear constraints on parameters. For this model with a unit root the restricted maximum likelihood estimator (RMLE) of the unit root is strongly consistent and it has the same limiting distribution as the ordinary least squares estimator of the unit root in an AR(1) model tabulated by Dickey and Fuller (1979). A modified RMLE is proposed which has the same limiting properties as the RMLE and is computationally much simpler. Simulation results show that our unit root tests based on the modified RMLE perform very well for small samples and compare favorably with the Said and Dickey (1985) tests with respect to both sizes and powers. An illustrative example from sample survey is given.  相似文献   
793.
从经济复杂性和进化性的理论出发,可建立一个基于主体的微观模拟模型,模拟量化经济转轨时期宏观经济政策促进经济有效增长和合理优化收入分配结构的经济效果,确定货币政策和财政政策在经济增长和收入分配效应的非对立性,为根据具体的经济形势和政策目标合理组合宏观政策提供依据。  相似文献   
794.
In the loss domain, both practical and ethical considerations rule out the systematic use of an incentive-compatible procedure involving real losses. The experimental study presented here aims at investigating whether some easier-to-implement procedure could be adequately used. For that purpose, the subjects’ degree of risk aversion is compared across three payment conditions: a real-losses condition based on a random-lottery (incentive-compatible) system, which serves as a benchmark, and two challengers, namely a “losses-from-an-initial-endowment” procedure and a hypothetical-losses condition. As a by-product, our experimental design also allows us to investigate the impact of monetary incentives in the gain domain. The main result is twofold: no significant difference arises between the three payment conditions in the loss domain, while real and hypothetical choices significantly differ in the gain domain. Our results suggest that the use of monetary incentives may be more crucial in the gain domain than in the loss domain.  相似文献   
795.
The purpose of this article was to verify whether beliefs about chance are multi or unidimensional constructs. Traditionally, authors who assessed beliefs about chance postulated that individuals who perceive themselves as unlucky usually believe that chance is random and are less confident as well as more anxious. Curiously, it appears that sometimes these individuals act as if they were motivated to avoid negative consequences. In order to better understand these puzzling findings, two studies were performed to compare three instruments intended to assess beliefs about chance and to verify their causal properties. In total, 285 students filled out a battery of instruments, including chance questionnaires (LOC, BIGL and MBIC) and personality traits. Overall, results showed that luck, through perceived controllability, seems to be related to volitional control, whereas chance, which is more stable and less controllable than luck, can be associated with cognitive distortions. The implications of these results are discussed.  相似文献   
796.
高校成本按其与在校学生人数的相互关系可以分为固定成本和变动成本 ,对固定成本应实行定额管理 ,对变动成本应实行定率管理 .努力降低高校成本是高等教育产业化的客观要求 ,对扩大办学规模、加强竞争力、减轻学生经济负担等方面 ,都具有重要意义  相似文献   
797.
798.
青兰高速(邯郸至涉县段)鼓山隧道属于三车道大跨度扁平隧道,围岩地质情况复杂,施工难度大,安全风险高,工期紧。通过超前大管棚进洞和建议性双侧壁导坑法、建议性单侧壁导坑法以及传统的台阶法等不同开挖方法,通过监控量测数据分析做保证,顺利完成施工任务,确保施工安全及质量。  相似文献   
799.
Density function is a fundamental concept in data analysis. Non-parametric methods including kernel smoothing estimate are available if the data is completely observed. However, in studies such as diagnostic studies following a two-stage design the membership of some of the subjects may be missing. Simply ignoring those subjects with unknown membership is valid only in the MCAR situation. In this paper, we consider kernel smoothing estimate of the density functions, using the inverse probability approaches to address the missing values. We illustrate the approaches with simulation studies and real study data in mental health.  相似文献   
800.
万舒晨 《统计研究》2021,38(6):116-127
为推动规模以下工业抽样调查工作以及解决当前调查面临的有关问题,本文对抽样设计进行了改进研究。首先,本文对规模以下工业抽样设计演变过程进行系统梳理,总结了现行抽样设计充分利用双重抽样框设计和综合运用三种抽样方法的特点。其次,针对园区层企业密度高的特点,探索结合园区因素改进地域抽样设计,对园区层和非园区层分别抽样,解决调查中面临的非抽样误差问题,并调整辅助变量使其与核心指标相关性均较高,确保抽样推断精度,有效提高抽样调查效率。并以我国东 部某省为例进行实证模拟得到结合园区因素抽样设计对调查工作改进的结论。再次,针对我国各级政府管理需要以及局队业务分工优化调整情况,介绍了规模以下工业样本追加理论和实证应用的主要研究成果。最后,在大数据时代数据来源广泛的背景下,本文在多重抽样框设计以及利用辅助变量提升样本轮换推断精度方面提出了进一步改进抽样设计的思路。  相似文献   
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