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11.
Using subjective well-being estimations, this study analyzes whether compensating variations vary across space using a cross-sectional data set from Chile. To achieve this goal, it describes and compares two econometric ways of modelling unobserved spatial heterogeneity. Both approaches allow compensating variations to vary across spatial units by assuming some distribution a priori. One method assumes that the spatial heterogeneity can be represented by a discrete distribution (a group of regions that share the same coefficient) and the other that the preferences can be represented by a continuous distribution (each region has a different coefficient). The results show that focusing just on the average estimates of compensating variations, as the applied studies have done so far, masks useful local variation. More empirical studies are needed to assess the advantages and disadvantages of both econometric approaches and how their results compare across a wide range of conditions and samples.  相似文献   
12.
Investors and financial markets have been a neglected stakeholder group in studies on a firm’s motivations to be socially and environmentally responsible. Despite being a strong driving force behind firm value, no study has investigated the influence of market and investor sentiments on CSR behaviour. Using a global sample, we investigate the effects of market and investor sentiments on firm CSR performance. We find negative market and investor sentiments in the prior year motivate firms to improve their CSR performance in the next year. We also find the magnitude of improvement in CSR performance differs not only by country, but by CSR sub-category as well. These findings imply that a firm’s motivation to improve its CSR performance is reactionary, rather than being driven by altruism. Regulators and proponents of CSR should thus seek to persuade investors and financial markets to put pressure on firms to further advance the CSR agenda.  相似文献   
13.
The complexity of value‐based management (VBM) is often not captured in empirical research. In particular, potential differences in the extent of VBM implementation are not considered. Firms are predominantly classified dichotomously into either VBM “adopters” or “non‐adopters.” In this study, we aim to fill this gap by introducing a framework to assess differences in the extent of VBM implementation (VBM‐sophistication) based on publicly available data. This approach enables us to study determinants of VBM‐sophistication based on a hand‐collected data set comprising 2,683 firm‐year observations from 16 European countries between 2005 and 2014. Specifically, we investigate (i) whether potential economic benefits associated with VBM implementation lead to a higher level of VBM‐sophistication, and (ii) if this relation is influenced by extra‐organizational institutions (e.g., industry norms). Our results indicate that companies exhibit higher VBM‐sophistication if certain firm characteristics that increase the potential economic benefits of VBM are present. Moreover, our study provides evidence that this effect is enhanced by extra‐organizational institutions that pressure and support firms in realizing the potential benefits of higher VBM‐sophistication.  相似文献   
14.
超奈奎斯特(Faster-than-Nyquist,FTN)速率传输可以有效提高频谱效率,但这种非正交传输方式引入的严重码间串扰相应提高了接收端的处理难度。针对该问题,设计了一种基于循环成块传输的低复杂度检测算法。最优检测被建模为无约束的二元二次规划(Boolean Quadratic Program,BQP)问题,为了求解该NP-hard问题,采用无穷范数约束松弛原问题的非凸可行解集,并基于次梯度下降法提出松弛问题的有效优化算法。数值仿真结果表明,所提算法在误比特率(Bit Error Rate,BER)性能上优于频域均衡,且在可接受的性能损失范围内算法执行效率远高于理论最优的最大似然序列估计(Maximum Likelihood Sequence Estimation,MLSE)。  相似文献   
15.
Finite mixtures offer a rich class of distributions for modelling of a variety of random phenomena in numerous fields of study. Using the sample interpoint distances (IPDs), we propose the IPD‐test statistic for testing the hypothesis of homogeneity of mixture of multivariate power series distribution or multivariate normal distribution. We derive the distribution of the IPDs that are drawn from a finite mixture of the multivariate power series distribution and multivariate normal distribution. Based on the empirical distribution of the IPDs, we construct a bootstrap test of homogeneity for other multivariate finite mixture models. The IPD test is applied to mixture models for matrix‐valued distributions and a test of homogeneity for Wishart mixture is presented. Numerical comparisons show that IPD test has accurate type I errors and is more powerful in most multivariate cases than the expectation–maximization (EM) test and modified likelihood ratio test.  相似文献   
16.
In this article we introduce a linear–quadratic volatility model with co-jumps and show how to calibrate this model to a rich dataset. We apply GMM and more specifically match the moments of realized power and multi-power variations, which are obtained from high-frequency stock market data. Our model incorporates two salient features: the setting of simultaneous jumps in both return process and volatility process and the superposition structure of a continuous linear–quadratic volatility process and a Lévy-driven Ornstein–Uhlenbeck process. We compare the quality of fit for several models, and show that our model outperforms the conventional jump diffusion or Bates model. Besides that, we find evidence that the jump sizes are not normally distributed and that our model performs best when the distribution of jump-sizes is only specified through certain (co-) moment conditions. Monte Carlo experiments are employed to confirm this.  相似文献   
17.
Good statistical practice dictates that summaries in Monte Carlo studies should always be accompanied by standard errors. Those standard errors are easy to provide for summaries that are sample means over the replications of the Monte Carlo output: for example, bias estimates, power estimates for tests and mean squared error estimates. But often more complex summaries are of interest: medians (often displayed in boxplots), sample variances, ratios of sample variances and non‐normality measures such as skewness and kurtosis. In principle, standard errors for most of these latter summaries may be derived from the Delta Method, but that extra step is often a barrier for standard errors to be provided. Here, we highlight the simplicity of using the jackknife and bootstrap to compute these standard errors, even when the summaries are somewhat complicated. © 2014 The Authors. International Statistical Review © 2014 International Statistical Institute  相似文献   
18.
针对多源信号关联难度大、关联准确率低的问题,利用同一目标平台上搭载的多个辐射源信号具有一致的动态变化趋势这一特点,提出一种利用相位差特征的多源信号关联方法。已知阵列形式和侦测点位置,通过对侦收到的多个辐射源信号进行处理,获取相位差信息并累积形成相位差变化趋势;对比提取疑似相似段,根据相似性判决策略进行有效关联。该方法能有效避免不同传感器对位置测量的误差影响,相比传统基于位置信息关联的方法,能有效提升关联准确率。仿真和实测数据分析证明了该方法的有效性,在阵列形式和侦测点位置已知的条件下该方法具有重要工程意义。  相似文献   
19.
This problem involves optimizing product collection and redistribution from production locations to a set of processing plants over a planning horizon. This horizon consists of several days, and the collection-redistribution is performed on a repeating daily basis. A single routing plan must be prepared for the whole horizon, taking into account the seasonal variations in the supply. We model the problem using a sequence of periods, each corresponding to a season. We propose an adaptive large-neighborhood search with several specifically designed operators and features. The results show the excellent performance of the algorithm in terms of solution quality and computational efficiency.  相似文献   
20.
A new kernel-type estimator for the distortion risk premiums of heavy-tailed losses is introduced. Using a least-squares approach, a bias-reduced version of this estimator is proposed. Under suitable assumptions, the asymptotic normality of the given estimators is established. A small simulation study, to illustrate the performance of our method, is carried out.  相似文献   
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