浅议当前农村养老保障体系中的缺陷和问题

目前农村家庭养老矛盾重重 ,面临农村养老保障由家庭养老向社会养老逐渐过渡的问题。在统筹社会养老基金时 ,应考虑农村养老保障体制转换成本问题 ,应由集体经济和国家负担部分转换成本。家庭养老以精神激励为主 ,但也要实行有效的监督。社会养老基金统筹可采用浮动制的收费办法 ,以弥补保费收缴水平偏低的矛盾     

需求分布规律变化情况下的报童订货策略

在需求分布规律变化情况下,报童在进行订货决策时会因为错误判断需求分布规律而导致期望库存成本增加。为了解决这一问题,本文集成传统历史需求信息和非传统需求信息以正确地认知需求分布规律,在此基础上决策订货量。假设需求服从均值不同、方差相同的两种类型的正态分布,每一种正态分布的概率已知。利用信号检测理论构建基于历史需求信息与需求分布概率的报童最优订货策略,并与只基于需求分布概率的直觉规则订货策略进行对比。结果表明：只要排除需求分布概率很大或很小两种极端情况,最优订货策略比直觉规则订货策略在控制期望库存成本方面的作用更明显,即利用历史需求信息可以有效修正报童对实际需求分布的检测结果,从而提高实际订货决策的准确性。研究结果对传统历史需求信息和非传统需求信息的集成以及需求信息交换等有一定的管理学启示和应用价值。     

基于双边减排成本信息不对称的排污权二级交易市场拍卖机制研究

本文构建了一个基于双边减排成本信息不对称的排污权二级交易市场拍卖模型,分析了统一价格、歧视价格及混合拍卖机制下卖方收益、排污权价格波动及排污权供给量差异,在此基础上给出了排污权二级交易市场最优拍卖机制,并进一步讨论了相关参数对最优拍卖机制的影响。结果表明：从收益最大化角度来看,最优的拍卖机制为歧视价格拍卖机制,但考虑到价格波动及排污权供给量等其他因素,排污权二级市场交易应选用混合拍卖机制。风险偏好变化对混合拍卖机制下卖方收益及价格波动的影响存在不确定性,当风险偏好超过某一阈值时,随着风险偏好程度增大,需求隐蔽效应占主导,收益及价格波动增大;相反,当风险偏好小于某一阈值时,随着风险偏好程度增大,竞争效应占主导,收益及价格波动减小。价格变动的供给影响系数对卖方收益的影响随买方参与人数的不同而不同。当买方参与人数较小时,需求隐蔽效应占主导,竞争效应不明显,随着价格变动的供给影响系数增大,混合拍卖机制下卖方的收益不断增加;当买方参与人数较大时,卖方收益同时受到需求隐蔽和竞争效应影响,随着价格变动的供给影响系数增大,收益呈先增大后减小趋势。随着价格变动的供给影响系数增大,价格波动呈先增大后减小趋势。     

Psychometric properties of the “parent-child relationship inventory” (PCRI) in a portuguese forensic sample

In Portugal, there is a gap regarding psychological tests validated for forensic contexts, particularly those related to child custody issues. The Parent–Child Relationship Inventory (PCRI) is one of the most used instruments in child custody contexts. This study aimed to analyze the psychometric properties of PCRI in a Portuguese forensic sample. PCRI factorial structure and psychometric properties were analyzed in a sample of 144 parents involved in child custody assessments. The questionnaire showed good internal consistency, except for the parental support, autonomy, and role orientation scales. It also showed good discriminant capacity. The confirmatory factor analysis did not replicate the 7-factor model proposed by Gerard. The results were discussed based on the use of PCRI in the context of child custody assessment.     

我国股东代表诉讼实用性的经济学分析

设置股东代表诉讼的目的是为了完善公司治理,强化股东的经营监督和抑制违法的作用。但由于股东提起代表诉讼是为了公司和全体股东的利益,如何降低原告股东的诉讼成本对实现股东代表诉讼的立法目的具有重要的意义。     

债权治理初探

负债不仅是企业融通资金的一种方式,还具有公司治理功能。不同种类、期限、优先权的负债,其公司治理效率是不同的。债权治理是指企业债权人作为公司治理主体之一对企业实施的治理。债权治理的方式主要有合同治理、流动性治理和控制权治理等。为了改善和提高我国公司治理效率,实现债权治理,应当建立有效的破产机制、推进国有商业银行的公司化改革、大力发展公司债券市场以及优化企业负债结构,创新负债融资工具等。     

对城市生活垃圾回收的质疑与思考

随着工业化和城市化的快速发展,城市生活垃圾问题作为影响城市可持续发展的重要制约因素日趋突出。大多数国家和地区都把垃圾回收作为减轻垃圾处理负担及保护自然资源和环境的有效模式而大力推广。但国内外大量的实证研究发现,垃圾回收是一种成本高昂的垃圾治理模式,不具有成本有效性。垃圾治理应从源头上减少垃圾的数量和提高产品的重复使用率,政府应减少强制性的垃圾回收,而将政策转向征收适度的垃圾填埋税(费)。     

An upper bound on the minimal total cost of the transportation problem with varying demands and supplies

In general cases, to find the exact upper bound on the minimal total cost of the transportation problem with varying demands and supplies is an NP-hard problem. In literature, there are only two approaches with several shortcomings to solve the problem. In this paper, the problem is formulated as a bi-level programming model, and proven to be solvable in a polynomial time if the sum of the lower bounds for all the supplies is no less than the sum of the upper bounds for all the demands; and a heuristic algorithm named TPVDS-A based on genetic algorithm is developed as an efficient and robust solution method of the model. Computational experiments on benchmark and new randomly generated instances show that the TPVDS-A algorithm outperforms the two existing approaches.     

Coordinating contracts for a financially constrained supply chain

We consider a financially constrained supply chain in which a supplier (leader) sells products to a retailer (follower) who has no access to bank financing due to her low credit rating. However, the supplier can borrow from a bank and offer trade credit to the retailer to alleviate her financial constraint. Failure to pay off a bank loan or trade credit incurs a variable default cost. We analyze the centralized version of the supply chain to obtain new coordination requirements. We then examine whether revenue-sharing, buyback, and all-unit quantity discount contracts can coordinate our supply chain. We show that the all-unit quantity discount contract fails to coordinate. However, the revenue-sharing and buyback contracts can coordinate the supply chain, but only when the supply chain has a sufficient total working capital. Moreover, they cannot allocate profit flexibly unless the supplier has a large enough working capital. Finally, we design a generalized revenue-sharing contract that coordinates the supply chain with flexible profit allocation, and also show by numerical examples its superiority over the revenue-sharing and buyback contracts.