Measuring benefits from spatially-explicit surface water quality improvements: The roles of distance,scope, scale,and size

Programs to improve water quality do not improve all water bodies equally. Evaluation of the benefits of such programs must account for where improvements occur and the relative magnitude of improvements that occur in different places. This study uses a choice experiment survey to explore how the value to a household of a surface water quality improvement varies as a function of (i) the distance between the household and the affected streams and rivers, (ii) the degree to which the quality of the water has been improved, (iii) how many stream and river miles have been improved, and (iv) the sizes of the affected streams and rivers. Results show evidence that value declines with distance in an approximately linear way, weak evidence that large rivers are worth more than small rivers, and no evidence that willingness-to-pay is nonlinear in either the degree of water quality improvement or the number of stream miles improved. These results indicate that it may be defensible in applied work to value small, spatially-explicit water quality improvement projects independently and then sum over projects.     

突发公共事件对电影行业影响的量化研究

人工收集和整理2012—2018年在中国市场上映的首轮院线电影信息数据，构建电影需求的嵌套logit回归模型，以新冠肺炎疫情为准自然实验，来量化突发公共事件对电影行业复产复工的影响。结果显示：第一，关于上映时间选择，在恢复营业后，如果所有因为疫情尚未上映的电影选择顺延上映能有效避免过度竞争的局面。第二，关于上映节奏控制，控制好未定档电影的上映节奏，保持适当的竞争能促进经济效益提升。其中，从11月份开始以每周两部的频率上映未定档电影的经济效益最佳。第三，关于上映方式选择，与线下播放相比，疫情期间选择线上播放能及时收回成本并有利于经济收益最大化的实现。研究结论为电影行业制定复产复工策略提供依据，为未来应对突发公共卫生事件提供参考。     

COVID-19, stock market and sectoral contagion in US: a time-frequency analysis

We assess the conditional relationship in the time-frequency domain between the return on S&P 500 and confirmed cases and deaths by COVID-19 in Hubei, China, countries with record deaths and the world, for the period from January 29 to June 30, 2020. Methodologically, we follow Aguiar-Conraria et al. (2018), by using partial coherencies, phase-difference diagrams, and gains. We also perform a parametric test for Granger-causality in quantiles developed by Troster (2018). We find that short-term cycles of deaths in Italy in the first days of March, and soon afterwards, cycles of deaths in the world are able to lead out-of-phase US stock market. We find that low frequency cycles of the US market index in the first half of April are useful to anticipate in an anti-phasic way the cycles of deaths in the US. We also explore sectoral contagion, based on dissimilarities, Granger causality and partial coherencies between S&P sector indices. Our findings, such as the strategic role of the energy sector, which first reacted to the pandemic, or the evidence about predictability of the Telecom cycles, are useful to tell the history of the pass-through of this recent health crises across the sectors of the US economy.     

Information flow between prediction markets,polls and media: Evidence from the 2008 presidential primaries

Are the forecast errors of election-eve polls themselves forecastable? We present evidence from the 2008 Democratic Party nomination race between Barack Obama and Hillary Clinton showing that the answer is yes. Both cross-sectional and time series evidence suggests that market prices contain information about election outcomes that polls taken shortly before the contests do not. Conversely, election surprises relative to polls too Granger cause subsequent price movements. We then investigate whether the additional information in prices could come from the media coverage of these campaigns, and uncover a set of complex relationships between pollster’s surprise, price movements, and various aspects of media coverage. Prices anticipate the balance and content of media coverage, but not the volume. On the other hand, it is the volume of media coverage, not the balance or content, that anticipates the surprise element in election outcomes. Moreover, Granger causality between prices and election surprises barely changes after controlling for media coverage, and causality from media volume to surprises persists too after controlling for price movements. Taken together, the results suggest that both prices and the volume of media coverage contain independent election-relevant information that is not captured in polls.     

Panel LM unit root tests with level and trend shifts

This paper considers a Lagrange multiplier (LM) based panel unit root test that allows for heterogeneous structural breaks in both the intercepts and slopes of a series. We note that many popular time series variables are likely to exhibit changing means and/or trends over time. Given that the usual tests will depend on the nuisance parameters indicating the locations of the trend breaks, we adopt a transformation procedure that makes our new panel unit root tests invariant to the nuisance parameters. To illustrate the importance of the power gain provided by our test, we examine the convergence hypothesis using relative ratios of per capita health care expenditures in 20 OECD countries. Our results provide evidence that the convergence hypothesis is supported.     

Time and frequency domain causality Testing: The causal linkage between FDI and economic risk for the case of Turkey

This study aims to explore the causal relationship between economic risk and foreign direct investment (FDI) inflows for the case of Turkey. With the aim of establishing robust findings for the research in mind, both traditional and modern causality techniques are utilized; time domain Granger (1969, “Investigating Causal Relations by Econometric Models and Cross-Spectral Methods.” Econometrica 37: 424–438.), Toda and Yamamoto (1995, “Statistical Inference in Vector Autoregressions with Possibly Integrated Processes.” Journal of Econometrics 66 (1–2): 225–250.), Fourier Toda-Yamamoto and frequency domain Breitung and Candelon (2006, “Testing for short- and long-run causality: A frequency-domain approach.” Journal of Econometrics 132 (2): 363–378.) spectral causality test. Our empirical findings reveal that; economic risk changes in Turkey significantly lead to changes in FDI inflows. However, there is no evidence of causality running from FDI to economic risk. The findings imply that economic risk is an essential determinant of FDI inflows in Turkey. Our findings are compatible with historical macroeconomic developments in Turkey and imply important policy implications. The results of this study can be generalized for other emerging economies that have similar macroeconomic environments, in order to create useful policy implications regarding FDI inflow.     

社保基金持股与企业盈余质量:A股上市公司的证据

本文利用中国A股上市公司2006-2015年的数据,研究社保基金持股对上市公司盈余质量的影响。我们用上市公司财务重述作为测度盈余质量的指标,发现社保基金持股能够显著降低企业发布财务重述的概率,这表明社保基金对上市公司盈余质量的提高具有促进作用。并且,社保基金的这一治理作用在国有企业、内部治理水平较差以及市场化程度较低地区的上市公司中更加显著。通过双重差分模型和安慰剂检验等方法弱化了内生性问题之后,以上结论依然成立,说明社保基金持股和盈余质量提升之间存在因果关系,我们称之为社保基金的公司治理作用。进一步研究发现,社保基金可以通过抑制控股股东资金占用、增加机构调研次数等途径提升被持股公司的盈余质量。本文有助于认识和评估社保基金持股对于上市公司的监督与治理作用。     

‘Whatever it takes’ and the role of Eurozone news

This letter shows that the ‘Whatever it takes’ speech by ECB President Draghi on 26 July 2012 and the ensuing installation of the Outright Monetary Transactions’ framework are associated with a reduction in the domestic and cross-border effect of Eurozone news on absolute yield changes in Eurozone sovereign debt. These results are consistent with the popular view that these actions helped to avoid a collapse of the Eurozone.     

Distribution of residual autocorrelations for multiplicative seasonal ARMA models with uncorrelated but nonindependent error terms

In this paper, we consider portmanteau tests for testing the adequacy of multiplicative seasonal autoregressive moving‐average models under the assumption that the errors are uncorrelated but not necessarily independent. We relax the standard independence assumption on the error terms in order to extend the range of applications of the seasonal autoregressive moving‐average models. We study the asymptotic distributions of residual and normalized residual empirical autocovariances and autocorrelations under weak assumptions on noise. We establish the asymptotic behavior of the proposed statistics. A set of Monte Carlo experiments and an application to monthly mean total sunspot number are presented.     

基于多软件平台的机电液一体化虚拟试验方法

提出一种针对复杂机电液系统的虚拟仿真试验方法,分别在ADAMS、AMESim、MATLAB/Simulink软件中建立机械子系统、液压子系统和控制子系统模型,并基于软件间接口技术,建立动态数据共享通道,实现系统的全面仿真分析,为系统设计与优化、控制策略选择等提供依据.该方法对于复杂机电液系统仿真分析具有普遍适用性,对缩短产品开发周期、降低产品研发成本、减轻仿真工作复杂性具有重要意义.