A two-sided model of paid peering

Internet users have suffered collateral damage in tussles over paid peering between large ISPs and large content providers. Paid peering is a relationship where two networks exchange traffic with payment, which provides direct access to each other’s customers without having to pay a third party to carry that traffic for them. The issue will arise again when the United States Federal Communications Commission (FCC) considers a new net neutrality order.We first consider the effect of paid peering on broadband prices. We adopt a two-sided market model in which an ISP maximizes profit by setting broadband prices and a paid peering price. We analytically derive the profit-maximizing prices, and show that they satisfy a generalization of the well-known Lerner rule. Our result shows that paid peering fees reduce the premium plan price, increase the video streaming price and the total price for premium tier customers who subscribe to video streaming services; however, the ISP passes on to its customers only a portion of the revenue from paid peering. ISP profit increases but video streaming profit decreases as an ISP moves from settlement-free peering to paid peering price.We next consider the effect of paid peering on consumer surplus. We find that consumer surplus is a uni-modal function of the paid peering fee. The paid peering fee that maximizes consumer surplus depends on elasticities of demand for broadband and for video streaming. However, consumer surplus is maximized when paid peering fees are significantly lower than those that maximize ISP profit. However, it does not follow that settlement-free peering is always the policy that maximizes consumer surplus. The peering price depends critically on the incremental ISP cost per video streaming subscriber; at different costs, it can be negative, zero, or positive.     

Analyzing quantile spillover effects among international financial markets

This paper investigates the quantile-based spillover effects among 17 stock markets from January 1993 to January 2022, utilizing a quantile approach based on the variance decomposition of a quantile vector autoregression (QVAR) model. Compared with the traditional mean-based spillover measures, this new quantile approach allows for a nuanced investigation of spillovers at every quantile and capture spillovers under extreme events. The results show that: (1) the total spillover is high and exhibits strong time-varying characteristics, and the tail spillover is higher and more complex in scale and direction; (2) the spillover at each quantile level shows an upward trend, especially during the 2008 crisis and the COVID-19 epidemic; (3) developed countries (or regions) are the net exporters of stock market spillovers, while the developing countries are the net importers; and (4) the 17 stock markets constitute different local financial networks, which may be related to economic conditions and geographical location.     

Municipal fiber in the United States: A financial assessment

Despite growing interest in broadband provided by municipally owned and operated fiber-to-the-home networks, the academic literature has yet to undertake a systematic assessment of these projects' financial performance. To fill this gap, we utilize municipalities' official reports to offer an empirical evaluation of the financial performance of every municipal fiber project in the U.S. operating in 2010 through 2019. An analysis of the actual performance of the resulting fifteen-project panel dataset reveals that none of the projects generated sufficient nominal cash flow in the short run to maintain solvency without infusions of additional cash from outside sources or debt relief. Similarly, 87% have not actually generated sufficient nominal cash flow to put them on track to achieve long-run solvency. In addition, 73% generated negative nominal cash flow over the past three fiscal years, leaving them poorly positioned to make up their deficits and causing them to fall farther into debt. An assessment based on the net present value of these projects' operating cash flow indicates that 53% of projects would not be on track to breakeven even assuming the theoretical best-case performance in terms of capital expenditures and debt service. Close analysis of these projects’ performance reveals that revenue generation likely plays a more important role in generating cash flow than efficiency in construction costs or operating efficiency.     

地方官员涉农经历对农产品质量安全水平的空间溢出效应研究——来自中国地级市的证据

在农产品质量安全属地管理的背景下,从第一责任人地方官员视角研究农产品质量安全具有现实意义。文章基于2008-2018年中国地级市数据样本,结合烙印理论,从地区间策略互动视角研究了地方官员涉农经历对农产品质量安全水平的影响及空间溢出效应。研究发现:第一,使用零膨胀泊松模型检验显示,有涉农经历的地方官员对本地区的农产品质量安全水平的提升存在显著的正向影响,且这种正向影响具有持续性,并随着地方官员涉农程度的增加影响更加明显;第二,使用空间杜宾模型实证表明,地方官员涉农经历对邻近地区的农产品质量安全水平也具有正向的空间溢出效应;第三,进一步研究发现,在不同的经济规模、农业发展和农产品质量安全水平下,地方官员涉农经历对邻近地区的农产品质量安全水平空间溢出效应存在异质性,不同类型的涉农经历中乡镇工作经历的空间溢出影响最为显著。研究结果从地方官员的角度对提升区域农产品质量安全水平提供了理论支持和经验依据,可以通过涉农经历官员的交流任职或加强对官员涉农经历的培养,以期提升区域农产品质量安全水平。     

现代西方国防经济学及其在中国的发展综述

现代国防经济学是现代经济学分支学科之一,与其他分支学科一样已经发展成为非常成熟的学科,但由于这门学科本身研究对象的特殊性,以及这门学科在中国发展的滞后性,使得国内经济学界对这门学科的历史及其在中国发展的现状缺乏了解.本文力图介绍现代西方国防经济学研究的现状,并回顾中国国防经济学的发展历程,旨在使国内主流经济学界对这门学科及其在中国的发展予以关注,并参与到这门学科的研究中来.     

铁路营业线施工一体化管理系统设计研究

为提高铁路营业线施工管理水平,在阐述铁路营业线施工管理现状的基础上,提出铁路营业线施工一体化管理系统总体设计方案。通过分析系统设计思路及目标、系统总体架构设计及系统与外部系统之间的接口关系,从施工一体化协同管理平台和施工基础资料管理2方面提出构建施工一体化管理的核心基础支撑,探讨施工计划管理、施工命令管理、施工登销记和施工安全防护管理等功能设计方案。研究基于施工一体化协同管理平台提供的统一资源描述、信息动态采集、冲突检测和综合监控实现铁路营业线施工一体化管理系统设计,可全面提高施工维修计划编制质量,提升营业线施工管理和施工安全防护水平,实现铁路营业线施工一体化管理、专业协同、多级联动。     

Stock market reactions to US Consumer Product Safety Commission enforcement actions

This study examines stock market reaction to violations of product safety regulations and firm product responsibilities in the post-enforcement period. Our event study results show that market reaction was negative to failures by firms to report product defects in a timely way. Our results also show that the stock market reaction varies depending on the type of violations, and whether there are single or multiple violations. Firms spend more on research and development and advertising in the post-enforcement period, in addition to investing in their compliance programmes which have a significant positive impact on product responsibility stewardship. Our empirical results show that the stock market reacts negatively to recall volume and refund remediation strategy. The stock market reaction is negative to social media communication about product recalls initiated by manufacturers. However, this negative effect appears to be counteracted by the positive corporate social responsibility (CSR) reputation effect of the manufacturers. Our findings imply that US manufacturing firms dealing with product recalls must be sensitive to how consumers and investors interpret the communication.     

几内亚马西铁路限制坡度方案研究

几内亚马西铁路是服务于西芒杜矿区企业铁矿石产品的铁路外运的重要基础设施,其限制坡度的确定是影响线路走向的主要技术标准,同时对工程投资、建设规模、运输能力、运营效果及行车安全性等至关重要。在阐述马西铁路现状的基础上,对马西铁路限制坡度取值范围进行估算,提出6‰/9‰均衡坡方案、6‰/13‰均衡坡方案、9‰/13‰均衡坡方案3种限制坡度方案,分析影响马西铁路限制坡度选择的主要因素,并通过车流特点、沿线地形地貌、机车类型、牵引质量、工程适应性及投资等方面对不同坡度方案进行分析比选,在满足研究年度运输需求前提下采用综合费用现值法,推荐采用6‰/9‰分方向选择限制坡度的均衡坡方案,研究成果对国内外货运铁路限制坡度的选择具有一定的指导和借鉴意义。     

和胃解毒汤治疗食道癌患者的疗效和安全性

目的探讨和胃解毒汤治疗食道癌患者的疗效以及安全性,为临床治疗食道癌提供新思路。方法选取2019年1月至2020年5月梅州市人民医院收治的食道癌患者62例作为研究对象,按照不同的治疗方案分为对照组(30例)和试验组(32例)。对照组给予调强适形放射治疗加紫杉醇(TXL)联合洛铂(LBP)化疗,即TP化疗方案;试验组在对照组基础上加用和胃解毒汤。比较分析两组患者的治疗效果,并评价两组患者的胃肠道不良反应发生情况。结果试验组治疗有效率及疾病控制率分别为78.13%和87.50%,显著高于对照组的53.33%和66.67%,差异有统计学意义(P<0.05);主要不良反应为胃肠道反应,以恶心呕吐、食欲下降为主,可耐受,其中试验组胃肠道不良反应发生率9.38%,显著低于对照组的30.00%(P<0.05)。结论和胃解毒汤在食道癌患者综合治疗中具有良好的疗效,减轻了不良反应,对治疗食道癌有积极的意义。     

基于随机Petri网的区块链舆情存证系统建模与效能分析

在重大突发公共危机事件期间,网络舆情常常面临谣言成本低、证伪不及时、溯源成本高、举证难度大的困局。为了应对这一网络舆情治理困局,本文从"区块链+网络舆情治理"视角出发,试图通过构建可信的、有约束力的舆情上链存证机制形成对虚假网络信息的技术震慑。本文引入随机Petri网的理论,构建区块链舆情存证系统模型,并通过仿真模拟对该模型的平衡状态与效能演变规律进行检验,从最佳优化环节、最佳增效尺度与系统自适应能力三个方面加深学界与业界对区块链舆情存证系统的理解,为我国应用区块链技术改善网络舆情治理能力提供参考。