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1.
Past forecast errors are employed frequently in the estimation of the unconditional forecast uncertainty, and several institutions have increased their forecast horizons in recent times. This work addresses the question of how forecast-error-based estimation can be performed if there are very few errors available for the new forecast horizons. It extends the results of Knüppel (2014) in order to relax the condition on the data structure that is required for the SUR estimator to be independent of unknown quantities. It turns out that the SUR estimator of the forecast uncertainty, which estimates the forecast uncertainty for all horizons jointly, tends to deliver large efficiency gains relative to the OLS estimator (i.e., the sample mean of the squared forecast errors for each individual horizon) in the case of increased forecast horizons. The SUR estimator is applied to the forecast errors of the Bank of England, the US Survey of Professional Forecasters, and the FOMC.  相似文献   
2.
Vietnam has undergone market reforms over the last three decades; and as a consequence, the coffee sector has become increasingly market‐driven. The success of the government's liberalisation policies in terms of market efficiency is investigated by examining the transmission of both positive and negative price changes for Robusta coffee between export and farmgate prices. We used a threshold vector error correction model and high‐frequency daily data. The primary result here is that of a symmetric price transmission between export and farm‐level prices. This result holds when tested with weekly price data, derived from the daily data. Farmgate prices respond faster to decreases than increases in export prices when the long‐run deviation exceeds a certain threshold. These price changes are transmitted within several days. This research also confirms the importance of transaction costs, and other price frictions mostly ignored in prior analyses for coffee.  相似文献   
3.
《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   
4.
[目的]通过对我国北方地区大规模生猪养殖技术效率进行测度,以期发现影响其技术效率增长的主要因素,为我国现阶段生猪养殖业战略性区划调整"南猪北进"工作提供实践指导和理论支持。[方法]根据随机前沿分析方法 (SFA)基本原理,运用对数型柯布—道格拉斯生产函数及我国北方大规模生猪养殖数据构建中国北方大规模生猪养殖随机前沿分析模型,对我国北方大规模生猪养殖技术效率进行测度并据此提出相关建议。[结果]北方地区大规模生猪养殖技术效率值纵向上来看整体在不断下降,而从地域上来看内蒙古自治区和东北地区技术效率值较高,北京与西北地区技术效率值较低。[结论]内蒙古自治区与东北地区适宜作为大规模生猪养殖承载地,与国家政策具有一致性;华北地区与西北地区大规模生猪养殖技术效率测度值较低,存在较大改进空间;针对该现状提出构建经济效益与环境保护并重的规模生态生猪养殖体系。  相似文献   
5.
Using the workweek of capital as a measure of capital utilization, we empirically test whether news shocks actually increase capital utilization. To this end, by estimating a panel VAR on two-digit manufacturing data identifying news shocks as innovations to stock returns orthogonal to the variations in current-period TFP growth, we find the positive response of capital utilization to news shocks. Moreover, to explain the positive response of capital utilization to news shocks in terms of plant-level investment behavior, we propose a heterogeneous plant model that combines the fixed cost of capital adjustment and an endogenous capital utilization choice. With the presence of fixed costs, except for the plants that have recently adjusted capital stock, news shock shortens the effective time horizon of currently installed capital stock and increases capital utilization. When the model economy is calibrated to match the salient features of the plant-level investment rate distribution, the economy generates a news-driven positive response of capital utilization.  相似文献   
6.
郑莹子 《价值工程》2021,40(2):79-80
国家环保治理政策的执行日益严格,多地地材价格明显上升,但铁路工程按照相关政策对地材价差不予调整,各施工单位在承接铁路工程项目时承担了巨大风险。铁路建设项目地材是否有必要进行调差,地材价差的计算、价差分担、合同签订以及验工计价等工作如何开展,均成为困惑建设单位以及施工单位的问题。本文就某铁路建设项目开工以来一直探索的地材调差问题进行探讨,为寻求解决同类问题的同行提供参考。  相似文献   
7.
高速移动环境下,无线信道具有时频双选性衰落的特性,使得滤波器组多载波(Filter Bank Multi-carrier,FBMC)系统产生长突发差错。将一种基于Baker映射的混沌交织算法应用在滤波器组多载波系统中,根据混沌密钥对发送数据进行分块和重新排列,按照Baker映射规则完成数据交织。此方法可以将长突发差错变为单突发差错,结合卷积编码能有效地纠正双选信道产生的长突发差错。仿真结果表明,在双选择信道中,基于混沌交织的滤波器组多载波系统误比特率性能优于传统基于块交织的滤波器组多载波系统。  相似文献   
8.
Abstract

Despite the strong evidence for the beneficial influence of resilience for employee stress resistance in domestic settings, the construct has not received much attention in the expatriation literature, where stress is considered a major factor for expatriates’ poor cross-cultural adjustment and turnover. Drawing upon conservation of resources theory, the present study examines resilience as an antecedent of expatriate work adjustment and turnover intentions. Furthermore, this study investigates the moderating role of perceived organizational inclusion climate as a resource-protecting organizational factor. Results from a survey of 175 expatriates in South Korea indicate that resilience is positively related to expatriate work adjustment and that these positive effects are more pronounced when expatriates perceive their organizational climate to be highly inclusive. Furthermore, findings suggest that work adjustment mediates the effects of resilience on turnover intentions and that this mediation is moderated by a perceived organizational inclusion climate. Implications for theory and practice are discussed.  相似文献   
9.
10.
[目的]新时期,加快推进南疆农业产业结构调整,促进农牧民全面实现脱贫致富奔小康,实现农业可持续发展,是推进南疆经济社会发展的重要手段。通过分析南疆地区水土资源条件和农业产业结构,提出推动南疆农业结构调整的发展方向和重点领域,并提出相应的政策建议。[方法]文章系统梳理南疆农业结构调整相关文献的基础上,通过实地调研和调阅南疆地区农业部门相关资料,全面分析南疆水资源利用、农牧业生产、农产品加工等方面面临的问题,提出针对性措施。[结果]南疆水资源处于过度开发状态,通过压减种植面积或调整种植结构节水空间十分有限,饲草料短缺矛盾较为突出,种养不平衡凸显,农产品加工业滞后,产业结构不合理。[结论]推进南疆农业结构调整,重点是加强水利工程建设提高骨干输水工程防渗率,发展高效节水农业,强化草畜配套平衡,大力发展农产品精深加工,推进农业产业化发展。  相似文献   
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