科技保险的困境—一个制度供求非均衡分析

现阶段，我国步入了创新驱动引领升级的关键时期，科技创新受到了整个社会的空前重视。科技保险作为分散和转移科技风险的重要手段，可以为科技创新提供有力的风险保障。目前，我国科技保险工作已经进入全面推广阶段，虽然取得了一定的成效，但整体运行并不理想，科技企业参保率低，科技保险缺失严重。究其原因，主要在于制度供给不能适应科技企业对科技保险的需求，科技保险制度供求非均衡，在现行的科技保险制度下积聚着大量的潜在利润，而这些潜在利润既是科技保险制度非均衡的原因，又是科技保险制度创新的动力。     

On hysteretic vector autoregressive model with applications

This paper proposes a new hysteretic vector autoregressive (HVAR) model in which the regime switching may be delayed when the hysteresis variable lies in a hysteresis zone. We integrate an adapted multivariate Student-t distribution from amending the scale mixtures of normal distributions. This HVAR model allows for a higher degree of flexibility in the degrees of freedom for each time series. We use the proposed model to test for a causal relationship between any two target time series. Using posterior odds ratios, we overcome the limitations of the classical approach to multiple testing. Both simulated and real examples herein help illustrate the suggested methods. We apply the proposed HVAR model to investigate the causal relationship between the quarterly growth rates of gross domestic product of United Kingdom and United States. Moreover, we check the pairwise lagged dependence of daily PM2.5 levels in three districts of Taipei.     

客户集中度、市场环境与存货管理效率

客户处在供应链的下游,对企业存货的采购、生产和销售都会产生重要影响,而多变的市场环境也在无形当中影响着客户与企业之间的关系。从企业所处行业、地区产品市场和客户三个角度所带来的市场环境变化入手,采用2011—2017年我国沪深两市A股制造业上市公司的数据,实证分析客户集中度与企业存货管理效率之间的关系。研究发现:(1)客户集中度越高,企业存货管理效率越高；(2)产品市场竞争力度越强,客户集中度对企业存货管理效率的影响越大；(3)产品市场发育越好,客户集中度对企业存货管理效率的影响越大。进一步研究发现,当企业因客户生产经营原因导致需求发生较大变化时,客户集中度对企业存货管理效率的正向影响更加显著。研究结论表明,政府应当注重市场竞争力的提升和良好经营环境的建设,使得企业在维护客户关系的同时充分发挥客户集中度对企业存货管理效率的积极作用。     

Bayesian inference for stable Lévy–driven stochastic differential equations with high‐frequency data

In this paper, we consider parametric Bayesian inference for stochastic differential equations driven by a pure‐jump stable Lévy process, which is observed at high frequency. In most cases of practical interest, the likelihood function is not available; hence, we use a quasi‐likelihood and place an associated prior on the unknown parameters. It is shown under regularity conditions that there is a Bernstein–von Mises theorem associated to the posterior. We then develop a Markov chain Monte Carlo algorithm for Bayesian inference, and assisted with theoretical results, we show how to scale Metropolis–Hastings proposals when the frequency of the data grows, in order to prevent the acceptance ratio from going to zero in the large data limit. Our algorithm is presented on numerical examples that help verify our theoretical findings.     

Application of a non-homogeneous Markov chain with seasonal transition probabilities to ozone data

In this work, we assume that the sequence recording whether or not an ozone exceedance of an environmental threshold has occurred in a given day is ruled by a non-homogeneous Markov chain of order one. In order to account for the possible presence of cycles in the empirical transition probabilities, a parametric form incorporating seasonal components is considered. Results show that even though some covariates (namely, relative humidity and temperature) are not included explicitly in the model, their influence is captured in the behavior of the transition probabilities. Parameters are estimated using the Bayesian point of view via Markov chain Monte Carlo algorithms. The model is applied to ozone data obtained from the monitoring network of Mexico City, Mexico. An analysis of how the methodology could be used as an aid in the decision-making is also given.     

双循环新发展格局下中国双向直接投资研究

构建以国内大循环为主体、国内国际双循环相互促进的新发展格局,是对未来中国经济发展路径做出的重大战略部署,作为连接国内国际双循环的纽带,双向直接投资的发展战略和路径面临重塑和调整。研究认为,应当以推动新时代科技创新和产业升级为目标,提高双向直接投资的质量,畅通供应链和产业链; 以“一带一路”倡议为依托,通过更高水平的双向投资带动中国与沿线国家贸易水平的提高; 建设高水平自贸区和自贸港,提高对外开放标准,更高质量吸引外资,提升参与国际大循环的技术含量和自主性; 在畅通要素流动领域,建立更加完善的现代化物流体系,建设更高标准的要素流通市场体系,降低制度性交易费用,提高生产率和对高质量外资的吸引能力。     

Impact of competitive conditions on supplier evaluation: a construction supply chain case study

This research proposes a multi-criteria decision-making (MCDM) framework and demonstrates the impact of competitive conditions on supplier evaluation process for construction supply chains. The paper focuses on the supply chain of a large-scale housing project in order to illustrate the role of competitive capability and suppliers’ profile and its influence on supplier evaluation based on prevailing supply/market conditions. Various scenarios are investigated to demonstrate the impact of competition on supplier evaluation. The contribution of the study lies in highlighting the impact of supply/market conditions on MCDM decisions causing supplier evaluation ‘imbalance’ and MCDM usage. It is expected that the study will be useful for project management, construction, supply chain management, sourcing professionals. The findings of the study are generalisable to projects-based situations such as petroleum refinery and ship building where bill of materials typically consists of thousands of items and a large number of suppliers are involved.     

基于混合CVaR的供应链绿色研发-广告决策与协调机制研究

针对消费者绿色偏好异质性而引发产品需求不确定性的情形，构建了基于混合CVaR准则的绿色供应链双层风险决策模型，研究了一个具有不同风险态度制造商与一个具有不同风险态度零售商所组成供应链的最优绿色研发投入及广告宣传水平等决策问题，分析了成员不同风险态度对供应链相关决策的影响。在此基础上，提出一个基于风险补偿的双向成本分担契约协调机制，并给出实现供应链协调的合理转移支付区间，最后通过数值分析验证该协调机制的有效性。结果表明，无论供应链成员表现为何种风险态度，该契约均能实现供应链协调，并且对由风险规避制造商与风险追逐零售商所组成的供应链协调效果最为显著。     

两级供应链中延保服务与基础质保服务交互策略

延保服务已成为商家获取高额利润的重要手段。本文以一个制造商和一个零售商组成的两级供应链为对象，分别在单主体（制造商或零售商）和两主体同时提供延保（偏向于制造商或零售商延保）情形下，研究最优延保定价、产品定价及延保与基础质保交互的决策。结果表明：维修成本直接影响延保的提供方式。仅制造商或零售商提供延保时，延保期限对基础质保期限有明显促进或抑制作用，且制造商提供延保有利于制造商和零售商。两者同时提供延保时，延保竞争促使其价格降低，且消费者偏向于某主体时，其延保价格相对高于另一方；基础质保与延保的交互关系取决于竞争程度。当消费者偏向制造商延保时，供应链各方所获取的利润较为稳健，相对高于单一主体提供延保情形时的利润。     

考虑消费者双重偏好的低碳供应链减排策略研究

为了削弱传统零售商在渠道博弈中的垄断地位，制造商尝试建立在线渠道与零售商展开竞争。本文在考虑消费者低碳偏好的基础上，又将消费者的渠道偏好进行区分，通过不同决策模式的对比及数值算例分析，寻求低碳供应链最优的减排边界。研究表明：1分散决策时，制造商的低碳决策会受消费者渠道偏好的影响；集中决策时，制造商的低碳决策保持不变。2不同决策模式的减排边界由渠道偏好决定，渠道偏好较大时，分散决策的减排边界更高；渠道偏好较低时，集中决策的减排边界更高；渠道偏好中立时，两者的减排边界相同。3制造商可以通过升级低碳技术、实行低碳化管理等方式降低减排成本，同时通过低碳产品认证、广告宣传等方式提高消费者对低碳产品的认可程度。