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1.
《Statistica Neerlandica》2018,72(2):90-108
Variable selection and error structure determination of a partially linear model with time series errors are important issues. In this paper, we investigate the regression coefficient and autoregressive order shrinkage and selection via the smoothly clipped absolute deviation penalty for a partially linear model with a divergent number of covariates and finite order autoregressive time series errors. Both consistency and asymptotic normality of the proposed penalized estimators are derived. The oracle property of the resultant estimators is proved. Simulation studies are carried out to assess the finite‐sample performance of the proposed procedure. A real data analysis is made to illustrate the usefulness of the proposed procedure as well.  相似文献   
2.
We show that speed limit policy, a monetary policy strategy that focuses on stabilizing inflation and the change in the output gap, consistently outperforms flexible inflation targeting and flexible price level targeting in empirical medium‐scale DSGE models under discretionary policymaking. In contrast to small‐scale New Keynesian models, this welfare ranking of the targeting frameworks is not overturned when inflation dynamics are mostly backward‐looking. Importantly, the performance of the speed limit policy shows less sensitivity to its parameterization than other frameworks that target the inflation rate or the price level.  相似文献   
3.
To achieve sustainable development, companies are increasingly putting an emphasis on the creation and the promotion of environmentally sustainable innovations. Environmentally sustainable innovation often involves a significant shift in a new strategic direction. This paper studies this shift from a dynamic capabilities perspective and aims to identify the microfoundations of science‐based companies' dynamic capabilities for high‐tech environmentally sustainable innovations. It investigates the development of high‐tech environmentally sustainable innovations in two distinctive science‐based companies. To scholars, this study provides an in‐depth process analysis, over time, of how and why microfoundations of dynamic capabilities influence the development of a science‐based company's high‐tech environmentally sustainable innovations. To practitioners in science‐based firms, this process study can function as a frame of reference, enabling the tailoring of a strategy for high‐tech environmentally sustainable innovation.  相似文献   
4.
针对高灵敏度接收机对频率合成器的高技术指标要求,构建了一种融合了直接模拟、直接数字以及间接数字的频率合成技术方案,根据该方案,成功实现了频率合成器的工程研制。通过测试,频率合成器相位噪声达-112 dBc/Hz@5 kHz,杂散抑制优于-75 dBc,频率分辨率小于1 kHz,10 MHz跳频时间约为13 μs,满足了高灵敏度接收机对频率合成器的高技术指标要求,为高纯度频率合成器的实现提供了一条新途径。  相似文献   
5.
为了更好地将人眼视觉感知特性应用于视频压缩系统,从而去除视频的视觉冗余成分,在利用像素域的恰可察失真(Just Noticeable Distortion,JND)阈值的基础上,结合JND阈值的空间相关性与图像块类型,提出了一种改进的残差滤波算法。该算法首先在像素域计算出每个像素的JND阈值,然后在变换单元(Transform Unit,TU)中挖掘每个像素JND阈值与其周围邻近像素JND阈值之间的空间相关性,再利用索贝儿(Sobel)边缘检测算子将TU分成不同类型的图像块,并且计算出对应的复杂度因子,最后结合上述像素JND阈值的空间相关性和TU复杂度因子对TU残差进行滤波。提出的算法模型可以嵌入到高效率视频编码(High Efficiency Video Coding,HEVC)框架。实验结果表明,在全I帧配置下,提出的算法与标准算法HM16.0相比,在人眼主观感知质量基本一致的情况下,平均可节省16.1%的码率。  相似文献   
6.
This paper constructs alternative balanced scorecards based on high‐performance work system (HPWS) and employment relations system (ERS) models. The models are depicted and compared in diagrams and used as framework skeletons for building separate HPWS and ERS scorecards, intended to provide a detailed data picture of the operational health and performance of an organization's employment/HR system and its operations, processes, and inputs/outputs. The scorecards are filled in with nationally representative data from 2,000+ U.S. workplaces using more than 50 employment/HR indicators, as reported by separate panels of managers and employees. The indicators for each workplace are aggregated into an overall HR/employment system score, ranked from low‐to‐high, and graphed as frequency distributions. These distributions provide a unique snapshot picture of the mean and dispersion of the state of employment relations and HR system performance for companies across the United State. They also reveal that “models matter” since the HPWS and ERS scorecards provide distinctly different evaluation assessments.  相似文献   
7.
促进中国经济高质量发展的必由之路是优化营商环境,提升区域竞争力。目前我国面临着国际内外的复杂局势,经济未来的发展趋势不容乐观,为此我们要深入落实新的发展理念,建立新的发展思路,构建新的发展格局。优化营商环境应实现建立服务型政府,实现企业经营环节的全覆盖,降低制度性交易成本、建立完善的商业系统生态链、打造具有中国特色的营商环境。  相似文献   
8.
This paper analyzes the impact of walking speed on tourist carrying capacity. To do so, a combination of simulation experimentation and on-the-ground experiment is suggested to work in a study case, Maiji Mountain Grottoes, China. The simulation findings indicate that walking speed has a negative impact on tourist carrying capacity and the correlation coefficient is 0.64, for the reason that walking takes up more space. The on-the-ground experiment shows that carrying capacity is not a unified limit all over a destination, but changeable temporally and spatially, and its estimation needs to be adjusted according to the minimum area required per tourist and tourist activity. The method applied in this paper and the simulation findings can serve as a methodological tool for further research about tourist carrying capacity where the main activity of tourists is walking while watching.  相似文献   
9.
文章以333名员工和68名主管在两时间点进行的配对调查为样本,基于群体卷入模型的研究视角,探析了高参与人力资源实践与员工前瞻行为之间的关系,对员工感知的高参与人力资源实践如何通过员工组织地位感知促进前瞻行为进行了研究。研究结果表明,员工感知的高参与人力资源实践能够正向预测员工的前瞻行为,而员工组织地位感知在这一关系中起完全中介作用。同时,员工主动性人格会削弱组织地位感知对前瞻行为的正向影响,即相对于高主动性人格的员工,主动性人格较低的员工更易受到由高参与人力资源实践导致的组织地位感知的正向影响,进而更多表现前瞻行为。  相似文献   
10.
This paper studies the residential segregation effects on educational attainment of children from regional migrant families in China. We find that if migrant families live in segregated communities with fewer local residents, the school dropout rate of the children living with their parents in the host cities is higher and their high school enrollment rate is lower. We employ a unique set of nationwide survey data of regional migrants in China in 2012 and 2013 that comprises more than 150,000 individuals in each year. We first use the ratio of migrants over the total population residing in a community to measure segregation. When the ratio increases by 10%, the school dropout rate of migrant children increases by 4.7% from the mean value. Secondly, we identify segregation from the housing type of the migrant family. When they reside in the dorms provided by their employers or in the workplace, they will also be surrounded by many migrant colleagues. We find that living in such places increases the “not‐going‐to‐high‐school rate” of migrant children by 35% from the mean value. Our subsample analysis indicates that the segregation effects only exist in the samples of male migrant children and rural hukou families.  相似文献   
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