New products or remanufactured products: Which is consumer-friendly under a closed-loop multi-level supply chain?

If the remanufactured and fresh products are in the market at the same price and quality, then it is difficult for the retailer to sell them all together simultaneously. There is differentiability in the market by the consumers even though they are of similar quality and price. These remanufactured products are the effect of a closed-loop supply chain. The closed-loop type supply chain problems have pulled much attention to tackling environmental and social issues for these remanufactured products. Based on the concern, a closed-loop formation of the supply chain is formulated with four players. Two types of quality are assigned for the manufactured and remanufactured products as remanufactured products maintain less quality than the newly manufactured products. The production system is imperfect, then all products are not perfect. A mathematical model with a multi-cycle closed-loop supply chain is discussed here, where the reworking process happens within the same cycle. An acceptance quality level influences the regaining rate of consumed products. The non-integrated phenomenon uses the inventory management policy operated by the vendor and the consignment-type stock policy. This mathematical problem is solved by employing algorithms, developed to achieve the local optimum (non-integrated situations) and global optimum (integrated situations). A numerical example and sensitivity analysis are provided to establish the mathematical model numerically. Results obtain that the retailer can tackle the situation in a proper way such that the closed-loop supply chain always is in profit. The profit is globally maximized, and the best results are obtained from different situations.     

Does migration raise agricultural investment? An empirical analysis for rural Mexico

The effect of remittances on capital accumulation remains a contested topic. This article uses a panel data set from rural Mexico to investigate the impact of remittances on agriculture and livestock investments. After controlling for the endogeneity of migration through an instrumental variable estimation our empirical results show that international migration has a significantly positive effect on the accumulated agricultural assets but not on livestock capital. This suggests that households use the capital obtained from international migration only to overcome liquidity constraints for subsistence production whereas migration itself seems to be the superior investment option compared to other productive activities such as livestock husbandry.     

Great expectations: Past wages and unemployment durations

Decomposing wages into worker and firm wage components, we find that firm-fixed components are sizeable parts of workers' wages. If workers can only imperfectly observe the extent of firm-fixed components in their wages, they might be misled about the overall wage distribution. Such misperceptions may lead to unjustified high reservation wages, resulting in overly long unemployment durations. We examine the influence of previous wages on unemployment durations for workers after exogenous lay-offs and, using Austrian administrative data, we find that younger workers are, in fact, unemployed longer if they profited from high firm-fixed components in the past. We interpret our findings as evidence for overconfidence generated by imperfectly observed productivity.     

基于聚类分析改进重要度分类的卡诺模型和6-I—S模型及其应用

文章在改进的卡诺模型的基础上,考虑到质量特性重要度,并应用系统聚类分析法改进了重要度分类,结果更加符合帕累托原理。接着将质量特性进一步细分,提出了基于聚类分析改进重要度分类的卡诺模型和6个区域的重要度一满意度模型（6-I—S模型）。以某型号空调为例说明了同时应用两个模型倾听顾客心声,能为企业进行质量改进提供更多有价值的信息。     

Macroeconomic control, political costs and earnings management: Evidence from Chinese listed real estate companies

Firms in China have faced high political costs during China’s economic transition, because they are affected by macroeconomic policies. However, research to date has offered no consistent conclusions on the relationship between political costs and earnings management in China. This study tests whether real estate firms attempt to decrease earnings during periods of macroeconomic control, using variables related to the national real estate market as proxies for political costs. We find that political costs are negatively related to earnings management in listed real estate firms. In addition, we find that non-state-owned enterprises utilized more income-decreasing accruals during this period. Our results are consistent with the political costs hypothesis.     

浅析IPsec在IPv6网络安全中的应用

本文针对IPv4当前采用的安全机制,分析了包括IPsec在内的几种网络安全机制。对网络而言IP的安全是非常重要的,本文通过分析网络攻击的原型以及IPsec在网络层保护IP的措施,提出如何在IPv6下的保护IP首尾安全。最后,介绍了针对IPsec的一些新的攻击模式。     

Lost in transition: the costs and consequences of sectoral labour adjustment

Abstract This paper uses an equilibrium search and matching model to study Canada’s sectoral labour adjustment in 2002–2006 during an increase in global commodity prices and exchange rate appreciation. I estimate economically significant adjustment costs for the aggregate economy in this episode and demonstrate that difficulty in transferring skills between jobs for individual workers can be an important contributor to these aggregate costs. The analysis also demonstrates that the level of unemployment benefits impacts the economy’s sectoral composition, its aggregate productivity, and the speed of its adjustment to shocks.     

Supply-side effects of exchange rates, exchange rate expectations and induced currency depreciation

Within the context of a small open economy model, this paper examines the repercussions of induced currency depreciation. The results presented in this paper are based on a model with firm microeconomic foundations and which takes into account both the supply and demand-side effects of exchange rate variations. The distinguishing feature of the model is the role of exchange rate expectations. We consider three kinds of expectations; adaptive, extrapolative, and regressive expectations. We also perform several sensitivity tests based on these expectations. Our simulation exercise shows that the effect of induced currency depreciation depends largely on supply-side effects. In most cases, we find that currency depreciation results in (i) a fall in output, (ii) an increase in prices and (iii) an improvement in the balance of trade. In the absence of weak supply-side effects of exchange rates, we find that, if the Marshall-Lerner conditions hold, then depreciation of the home currency has a favorable effect on output but its effect on the balance of trade is negative.     

Distributional impacts of a local living wage increase with ability sorting

I develop a model of ability sorting of low-wage workers across multiple markets when one market substantially increases its wage floor using a living wage. The wage floor increase can increase or decrease employment probabilities in both covered and uncovered markets.