Understanding the welfare effects of unemployment insurance policy in general equilibrium

This paper analyzes the welfare effects of unemployment insurance reforms in a general equilibrium incomplete market model. In particular, it decomposes the total welfare effect for each individual into different factors. I consider a model where the consumers face an uninsurable unemployment risk, can save in an interest-bearing asset, and are subject to a borrowing constraint. The labor market is modeled using a Diamond–Mortensen–Pissarides style search and matching model. The decomposition exercises reveal how each factor contributes to the heterogeneity of welfare effects among different consumers.     

MONETARY POLICY IN A NON‐REPRESENTATIVE AGENT ECONOMY: A SURVEY

It is well known that central bank policies affect not only macroeconomic aggregates, but also their distribution across economic agents. Similarly, a number of papers demonstrated that heterogeneity of agents may matter for the transmission of monetary policy to macro variables. Despite this, the mainstream monetary economics literature has so far been dominated by dynamic stochastic general equilibrium models with representative agents. This paper aims to tilt this imbalance towards heterogeneous agents setups by surveying the main positive and normative findings of this line of the literature, and suggesting areas in which these models could be implemented. In particular, we review studies that analyse the heterogeneity of (i) households’ income, (ii) households’ preferences, (iii) consumers’ age, (iv) expectations and (v) firms’ productivity and financial position. We highlight the results on issues that, by construction, cannot be investigated in a representative agent framework and discuss important papers modifying the findings from the representative agent literature.     

New technology and the urban environment

Technology has always had an influence on the form of settlements, but only since the coming of Information Technology has it aroused much interest from academics and planners. The impact that IT is likely to have on urban areas is debated, some foreseeing decentralisation and the end of place, while others see evidence of the centralisation of control in a global economy. Other new technologies may also affect cities as new materials provide the opportunity for different styles of building. As we enter the 21st century, however, we do so with the largest stock of urban capital ever, much of which is ageing and in need of maintenance. Technology is part of a complex interrelationship of influences on urban areas and much of it will have to be retrofitted on to the pre-existing environment.     

产品市场势力能降低股票市场的异质信念吗——基于A股市场的实证研究

基于2001年至2009年A股市场的数据,本文检验了Peress(2010)提出的产品市场势力降低股票市场异质信念水平的推断,并分析了Miller(1977)提出的影响股票市场异质信念的因素。我们发现产品市场势力不仅不能降低反而可能会提高股票市场异质信念的水平。在将异质信念分解为异质先验导致的异质信念,渐进信息流动、有限注意导致的异质信念后,这种提高主要表现在对后者的提高上。该结果意味着产品市场势力可能因为提高了异质信念水平而促进了股票市场的交易,从而为交易异象的解释提供了新的思路。此外,实证结果显示上市公司的业务集中度、机构持股可以降低异质信念水平,而上市公司的已上市时间、市场中股票数量对于异质信念的影响与已有的理论分析并不完全一致。     

一类多机种飞机油料加注问题的仿真研究

总结了国内相关人员关于作战飞机地面油料加注的研究,借助GPSSW仿真语言研究了多机种飞机单队列、多服务台、服务台可休假的油料加注模型,并在给定设施利用率范围的条件下得到科学合理的服务台数量分配结果。     

THE IMPACT OF GOVERNMENT EXPENDITURE ON GROWTH: EMPIRICAL EVIDENCE FROM A HETEROGENEOUS PANEL

This paper investigates the impact of government expenditure on growth, in a heterogeneous panel, for a sample of developing countries. Using generalized method of moments techniques, we show that countries with substantial government current expenditure have strong growth effects, which vary considerably across the nations.     

Global recessions as a cascade phenomenon with interacting agents

This paper examines global recessions as a cascade phenomenon. In other words, how recessions arising within one or more countries might percolate across a network of connected economies. An agent based model is set up in which the agents are Western economies. A country has a probability of entering recession in any given year and one of emerging from it the next. In addition, the agents have a threshold propensity, which varies across time, to import a recession from the agents most closely connected to them. The agents are connected on a network, and an agent’s neighbours at any time are either in (state 1) or out (state 0) of recession. If the weighted sum exceeds the threshold, the agent also goes into recession. Annual real GDP growth for 17 Western countries 1871–2006 is used as the data set. The model is able to replicate three key features of the statistical distribution of recessions: the distribution of the number of countries in recession in any given year, the duration of recessions within the individual countries, and the distribution of ‘wait time’ between recessions i.e. the number of years between them. The network structure is important for the interacting agents to replicate the stylised facts. The country-specific probabilities of entering and emerging from recession by themselves give results which are by no means as well matched to the actual data. We are grateful to an anonymous referee for some extremely helpful comments.     

Trade Credit Management and the Decision to Use Factoring: An Empirical Study

This paper examines the firm's decision to use factoring amongst a cross-sectional sample of 655 manufacturing companies using a rich firm-level database. The paper develops and tests hypotheses that explain this particular choice of credit and financial management policy. We find strong evidence of a 'financing demand' explanation for the use of factoring, and also some support for theories which relate the decision to use a factor to the firm's product characteristics, to market characteristics and to the preferences of the factor (supply constraints). The motivation to use factoring, however, appears to be related more to a demand for asset-based finance from small companies than to firm-level choices about organisational structure.     

A Formal Study of Distributed Meeting Scheduling

Automating routine organizational tasks, such as meeting scheduling, requires a careful balance between the individual (respecting his or her privacy and personal preferences) and the organization (making efficient use of time and other resources). We argue that meeting scheduling is an inherently distributed process, and that negotiating over meetings can be viewed as a distributed search process. Keeping the process tractable requires introducing heuristics to guide distributed schedulers' decisions about what information to exchange and whether or not to propose the same tentative time for several meetings. While we have intuitions about how such heuristics could affect scheduling performance and efficiency, verifying these intuitions requires a more formal model of the meeting schedule problem and process. We present our preliminary work toward this goal, as well as experimental results that validate some of the predictions of our formal model. We also investigate scheduling in overconstrained situations, namely, scheduling of high priority meetings at short notice, which requires cancellation and rescheduling of previously scheduled meetings. Our model provides a springboard into deeper investigations of important issues in distributed artificial intelligence as well, and we outline our ongoing work in this direction.