零工经济时代数字平台控制劳动力的供给行为

本文首先基于委托-代理模型构建了一个数字平台控制劳动力供给的行为经济学模型,从理论上分析了数字平台控制劳动的方式和心理机制;然后建立了一个赫克曼(Heckman)选择模型,利用Uber的大数据实证分析了网约车司机的劳动决策.研究结果表明:(1)在零工具有参考点偏好的前提下,数字平台通过高货币激励或高目标奖励使零工劳动者的参考点具有适应性,进而避免其过早地陷入“收入目标”行为;(2)数字平台利用零工劳动者的厌恶损失偏好,对其实施控制以延长工作时间;(3)网约车司机存在“收入目标”行为,且该行为呈现出动态性的特点;(4)收入激励和“峰时”溢价对网约车司机的工作概率和工作时间具有显著的正影响,且在一天的某个时间段内能够抑制网约车司机的“收入目标”行为.可见,零工经济时代到来,一方面提高了劳动力资源配置效率;另一方面,数字平台通过劳动控制变相延长了零工的劳动时间,加剧了剥削.     

利用大数据分析技术的智能化网络故障诊断系统

随着网络技术的快速发展以及各种新网络业务的出现，网络的规模日益扩大和复杂。同时，各种网络服务对于网络可靠性的要求也逐渐提高，这就对网络的维护提出了更高的要求。在这种情况下，传统的网络维护模式逐渐不能适应现代网络发展的需求。针对现代大型网络的故障诊断问题，利用大数据分析技术，设计并完成了一套整体的智能化故障诊断系统。在此系统中，针对不同的故障类型，利用能够获取到的数据类型，针对性地设计了相关的故障诊断模块和算法。系统整体基于开源的数据处理平台构建，具备良好的可扩展性。通过实际案例数据的验证，结果表明此系统具备良好的处理实际网络故障的能力，将大数据分析技术应用于网络故障诊断领域也具备较强的可行性。     

The impact of crude oil inventory announcements on prices: Evidence from derivatives markets

This study examines the impact of weekly crude oil storage announcements on oil futures and options prices. We document evidence of a strong announcement day effect on both markets, and find prices to move in anticipation of the inventory surprise. Futures returns significantly decrease with positive surprises and increase with negative surprises. There is no evidence of an asymmetric impact on futures prices. Near‐the‐money options exhibit the greatest price sensitivity, and the magnitude of the price response of both futures and options declines with maturity. The results remain robust even after controlling for various macroeconomic and other storage‐related news variables.     

延迟退休年龄下隔代抚育与劳动参与的抉择*——基于工资收入随机性假定的研究

隔代抚育会对延迟退休年龄政策在促进劳动力供给上产生挤出效应。为了对此进行验证，本文在工资收入随机性的假定及延迟退休5年的情景下，模拟了面临孙辈照护需求的女性临近退休者提前退休所产生的福利变化。进一步，本文采用CHIP和CHARLS的微观调查数据，对不同群组的收入增长率和收入风险进行了估计，继而分析了当面临孙辈照护需求时这些收入特征对退休决策者制度退休和退休后劳动参与抉择产生的影响。总体上，在延迟退休年龄政策下，隔代抚育将对女性劳动力供给产生挤出效应。当面临孙辈照护需求时，女性临近退休者的制度退休抉择主要受自身收入增长率和收入风险的影响，收入增长率越低，或收入风险越高，她们提前退休的意愿就越强烈；制度退休后的劳动参与则更多地受子女收入增长率的影响，子女收入增长率越高，劳动参与的概率越低。     

Institutional quality,investment efficiency,and the choice of public–private partnerships

We examine a sample of 625 public–private partnership (PPP) firms from 1980 to 2015 that straddle nine countries with varying degrees of economic development and PPP markets. We find that the motivations of the firms that undertake PPP investments vary. While private sector firms in economies with low institutional quality choose to engage in PPPs to alleviate capital constraints attributed to underinvestment, those in economies with high institutional quality participate in PPPs to solve the problem of overinvestment due to an abundant cash flow. In the long run, the benefits of lower capital constraints through PPP investments are more pronounced in economies with high institutional quality.     

Dynamic relationship between stock market trading volumes and investor fear gauges movements

This article applies multifractal detrended fluctuation analysis (MF-DFA) and multifractal detrended cross-correlation analysis (MF-DCCA) to investigate cross-correlation behaviours between two kinds of stock markets trading volumes and investor fear gauges covering the data of U.S. stock markets from 2 January 2004 to 31 July 2018. The empirical results show that the dynamic relationship between stock markets trading volume fluctuations and different kinds of investor fear gauges are multifractal and find that the dynamic relationship is strongly anti-persistent. Moreover, financial crisis in 2008 has a significant impact on the cross-correlated behaviour, suggesting that stock market trading volume fluctuations and investor fear gauges are more susceptible to each other during the financial crisis period. Through the rolling windows analysis, we also find that the stock markets trading volume fluctuations and different kinds of investor fear gauges are anti-persistent dynamic cross-correlated.     

污染源在线监测现状与优化建议

随着我国工业化进程的不断推进,在提升我国经济发展速度的同时,也带来了巨大的自然环境污染现象,特别是受到传统管理模式的影响,行业生产过程中缺乏环境保护意识,不仅造成了生产资源的大量浪费还在一定程度上影响了自然生态系统的可持续发展,对我国经济和自然生态均造成了极大损害.随着我国科技技术的不断发展和推进以及环保意识的增强,国家有关部门加大了环境保护管理的工作力度.本文主要分析污染源在线监测技术相关内容以及应用重要性,在分析存在的现状问题基础之上,开展污染源在线监测优化策略的探析,以期为我国环境保护工作提供一定参考价值.     

铁路建设项目地材调差的探讨

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。     

The effects of credit default swaps on corporate investment

ABSTRACT

This paper examines how credit default swaps (CDS) affect the corporate investment of the referenced entities. We document a significant reduction in corporate investment after CDS trading, a result that is robust to alternative model specifications and a set of endogeneity tests. Our findings of the increased firm risk and cost of capital support the costly external capital channel. The cross-sectional variations in CDS effects demonstrate that both reduced monitoring and the empty creditor problem might be the underlying forces driving the costly external capital channel. Our additional analysis implies that CDS trading is associated with an enhancement in investment efficiency for firms that are prone to overinvestment.     

港西油田注聚系统聚合物回收液地面处理工艺浅析

港西油田自2004年应用采出水注聚,随着注聚时间累积,聚合物溶液受地层矿化度影响,在井筒和近井地带堵塞,导致部分注聚井频繁出现压力高、注不进现象,这些高压注聚井在修井作业过程中会产生大量的聚合物废液,注聚系统产生的聚合物废液回收进入油水分离系统,底水含油明显升高,严重影响脱水效果.针对这一问题,研制出了一种采油用磺基聚合物降解剂-无机盐的破胶剂,该破胶剂现场应用效果十分显著,聚合物回收液粘度由15970MPa·s降至6-8MPa·s.