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1.
We identify farms’ optimal investment path in capital assets and compare it with their actual investment to assess the direction and extent of deviation from the optimal investment. A probit model is further used to investigate the determinants of the probability that a farmer over‐ or under‐invests in capital assets. We use a panel dataset of Dutch dairy farms over the period 2003–2013, and find that most farms under‐invest in capital assets during the study period. Although the number of farms that had over‐invested in capital assets is relatively small, these farms account for the biggest share of total investment in capital assets. The probit results show that liquidity, agricultural support payments, age, land tenure and standard output size are important variables explaining the likelihood of over‐and under‐investment.  相似文献   
2.
Recent methodological developments provide a way to incorporate the temporal dimension when accounting for spatial effects in hedonic pricing. Weight matrices should decompose the spatial effects into two distinct components: bidirectional contemporaneous spatial connections; and unidirectional spatio-temporal effects from past transactions. Our iterative estimation approach explicitly analyses the role of time in price determination. The results show that both spatio-temporal components should be included in model specification; past transaction information stops contributing to price determination after eight months; and limited temporal friction is exhibited within this period. These findings highlight the decidedly non-linear temporal patterns of such information effects.  相似文献   
3.
极点作为谐振区雷达目标的最主要电磁特性,具有很大的空间目标识别前景。但是在使用频域观测数据提取目标极点时,存在虚假极点和估计精度问题。针对上述问题,首先通过加窗和截断改进了后时响应信号的获取流程,抑制了虚假极点影响;然后采用最小描述长度法(MDL)估计极点个数,避免了定阶错误引起的虚假极点;最后采用联合矩阵束法估计极点,有效减少了单角度数据估计极点时存在的遗漏极点和虚假极点问题。FEKO软件验证表明,所提算法具有更高的精度和抗噪能力。  相似文献   
4.
淮扬历史文化悠久,塑造了独特的饮食文化,其"精""雅""养"的饮食文化特质,成为中国饮食文化中的独特元素.在新的时代环境之下实现新的发展,这是淮扬饮食文化发展的内在需求.本文立足淮扬饮食文化特点,分析了其发展中面临的问题,并在此基础之上,从推动饮食文化创新、推动饮食产业发展、打造市场品牌影响力、实施"饮食+"措施等方面,阐述了淮扬饮食文化发展的路径.  相似文献   
5.
当前,大众创业、万众创新已是时代最强音,论文通过对俄罗斯政府推进中小企业发展相关做法的得失进行评析,提出河北发展民营经济的路径和方法,力求为河北省民营企业高质量发展提供有益借鉴。  相似文献   
6.
The estimation of the parameters of a continuous-time Markov chain from discrete-time observations, also known as the embedding problem for Markov chains, plays in particular an important role for the modeling of credit rating transitions. This missing data problem boils down to a latent variable setting and thus, maximum likelihood estimation is usually conducted using the expectation-maximization (EM) algorithm. We illustrate that the EM algorithm is likely to get stuck in local maxima of the likelihood function in this specific problem setting and adapt a stochastic approximation simulated annealing scheme (SASEM) as well as a genetic algorithm (GA) to combat this issue. Above that, our main contribution is to extend our method GA by a rejection sampling scheme, which allows one to derive stochastic monotone maximum likelihood estimates in order to obtain proper (non-crossing) multi-year probabilities of default. We advocate the use of this procedure as direct constrained optimization (of the likelihood function) will not be numerically stable due to the large number of side conditions. Furthermore, the monotonicity constraint enables one to combine structural knowledge of the ordinality of credit ratings with real-life data into a statistical estimator, which has a stabilizing effect on far off-diagonal generator matrix elements. We illustrate our methods by Standard and Poor’s credit rating data as well as a simulation study and benchmark our novel procedure against an already existing smoothing algorithm.  相似文献   
7.
回顾了国家的林业政策,梳理了黑龙江国有森工企业的转型要素,分析了国有森工企业转型发展路径的影响因素。基于政企分开的政策因素与企业的发展需要,结合国有森工企业转型存在的现实问题,分别从企业转型能力、企业转型意愿和企业转型方向3个方面阐述政企分开政策对国有森工企业转型的驱动作用。在此基础上,提出在政企分开政策驱动下国有森工企业转型发展的实现路径,并从重新定位政府与市场关系、注重培育国有森工企业内部组织平台化转型路径和构建品牌转型路径3个方面进行国有森工企业转型发展的路径研究。  相似文献   
8.
社会文化因素在影响与制约劳资关系系统的运行中起着至关重要的作用, 尤其是具有高度稳定性和传承性的文化传统能够从深层次上指挥或引导制度变迁的发生及其走向,从而构建出不同类型的企业劳资关系。本文基于新制度经济学的制度变迁路径依赖理论,对日本“利益一致型”企业劳资关系演化中的文化路径依赖现象进行研究,认为“和”观念、集团意识、等级思想、“家”原理等文化传统深刻影响了企业伦理观、人性假设、企业文化类型、劳资博弈格局和劳资关系模式,是日本企业劳资关系演化中形成路径依赖现象的驱动性因素。在日本企业劳资关系的重建过程中,这种路径依赖规律会依然发挥作用,引导劳资模式向“利益协调型”演化。  相似文献   
9.
多径效应导致基于信号接收强度(RSSI)的室内定位方法精度不高,采用更细粒度的物理层信道状态信息(CSI)可以区分不同路径,提高定位精度。在已有基于CSI室内定位方法的基础上,通过改进对数距离路径损耗模型,得到CSI与传输距离的关系,并结合目标位置所测得的CSI值回归出目标与发射端的距离,最后通过三边定位法预测出目标的位置坐标。实验表明,相比基于RSSI的定位方法以及已有的基于CSI的定位方法,所提方法2 m以内的误差概率提高了将近40%和20%,有效提高了定位精度。  相似文献   
10.
This study investigates the level of risk due to fat tails of the return distribution and the changes of tail fatness (TF) through portfolio diversification. TF is not eliminated through portfolio diversification, and, interestingly, the positive tail has declining fatness until a certain level is reached, while the negative tail has rising fatness. This indicates that fat tails are highly relevant to common factors on systematic risk and that the relevance of common factors is higher for the negative tail compared to the positive tail. In the portfolio diversification effect, the declining fatness of the positive tail further reduces risk, but the rising fatness of the negative tail does not contribute to this effect. The asymmetry between the fatness of the positive and negative tails in the return distribution corresponds to the asymmetry of the trade-off relationship between loss avoidance and profit sacrifice that is expected as a consequence of portfolio diversification. Investors use portfolio diversification to reduce their risk of suffering high losses, but following this strategy means sacrificing high-profit potential. Our study provides empirical confirmation for the practical limitation of portfolio diversification and explains why investors with diversified portfolios suffer high losses from market crashes. An examination of the Northeast Asian stock markets of China, Japan, Korea, and Taiwan show identical results.  相似文献   
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