Linkage between international trade and economic growth in GCC countries: Empirical evidence from PMG estimation approach

This paper explores the empirical evidence of the links between economic growth and openness to international trade by controlling for auxiliary variables in the model for the six Gulf Cooperation Council (GCC) countries over the annual sample period 1980–2010. After testing for cointegration based on a recent bootstrap panel test, we employ the Pooled Mean Group (PMG) estimation technique of M.H. Pesaran, Y. Shin, and R. Smith (1999. “Pooled Mean Group Estimation of Dynamic Heterogeneous Panels”. Journal of the American Statistical Association 94: 621–634) that is appropriate for drawing sharper conclusions in dynamic heterogeneous panels by considering long-run equilibrium relations. The results show evidence of cointegration relationship between the variables of interest, and reveal that economic growth responds positively to trade openness over both the short run and long run. The evidence is robust to using various trade openness measures and to alternative model specifications, suggesting thus the non-fragility of the linkage between economic growth and openness to international trade for the GCC region. Our findings are then promising and support the view that economic growth is directly and robustly linked to trade openness for the GCC countries.     

Incomplete Information, Heterogeneity, and Asset Pricing

We consider a pure exchange economy where the drift of aggregateconsumption is unobservable. Agents with heterogeneous beliefsand preferences act competitively on financial and goods markets.We discuss how equilibrium market prices of risk differ acrossagents, and in particular we discuss the properties of the marketprice of risk under the physical (objective) probability measure.We propose a number of specifications of risk aversions andbeliefs where the market price of risk is much higher, and theriskless rate of return lower, than in the equivalent full informationeconomy (homogeneous and heterogeneous preferences) and thuscan provide an(other) answer to the equity premium and risk-freerate puzzles. We also derive a representation of the equilibriumvolatility and numerically assess the role of heterogeneityin beliefs. We show that a high level of stock volatility canbe obtained with a low level of aggregate consumption volatilitywhen beliefs are heterogeneous. Finally, we discuss how incompleteinformation may explain the apparent predictability in stockreturns and show that in-sample predictability cannot be exploitedby the agents, as it is in fact a result of their learning processes.     

The Sun Also Rises: Productivity Convergence Between Japan and the USA

The growth process for a technological leader is different from that of a follower. While followers can grow through imitation and capital deepening, a leader must undertake original research. This suggests that as the gap between the leader and the follower narrows, the follower must undertake more genuinely innovative R&D and possibly face a slower overall growth rate. The results of a dynamic panel equilibrium-correction model of productivity growth suggest that the productivity gap with the USA had a strong effect on the growth of Japanese manufacturing, and that changes in R&D intensity also made a significant contribution. Moreover, the effect of the productivity gap was significantly higher in industries that had higher R&D intensities, higher levels of human capital, and were more open to exports. This paper is based upon Chapter 5 of my D.Phil. thesis at the University of Oxford. It was partly written while I was a Visiting Scholar at the Foundation for Advanced Information & Research, Tokyo, and was supported by a Sanwa Bank Foundation Research Fellowship and ESRC grants R000234954 and R000237500.     

Consulting experts with vested interests: The power of benchmarking

A decisionmaker gets independent advice from two experts, who can be of two different types. Experts are risk-neutral and prefer certain policies irrespective of the state of nature, so to induce information-sharing the decisionmaker must reward truthful experts. I show that, in this environment, a heterogeneous committee has no informational advantage over a single expert: a decision rule that encourages one expert to be honest immediately makes honesty less attractive for the other. With a homogenous committee, the higher is the correlation between the experts’ signals, the more the decisionmaker is willing to pay to secure independent advice.Received: April 2004, Accepted: Accepted: January 2005, JEL Classification: D71, D82Lars Frisell: I thank David Austen-Smith, Tim Feddersen, Johan Lagerlöf, Jan Potters, Ken Shotts, Jonas Vlachos, Jörgen W. Weibull, an anonymous referee, and especially Karl Wärneryd for helpful comments. Financial support from the Jan Wallander and Tom Hedelius Foundation and the Sweden-America Foundation is gratefully acknowledged.     

A Chain-Type Price Index for New Business Jet Aircraft

This paper presents a price index constructed to measure the real price and real output of corporate business jet aircraft. It employs a chained price index methodology to properly account for the effect of changes in aircraft quality and product lines on the price index. The index indicates that the average price level of corporate jets has significantly outpaced the general price level measured by the GDP deflator, nearly doubling the real price of the product over a 35-year period from 1968 to 2003, which could have negatively affected the demand for the product. Because the GDP deflator significantly understates the price increase in corporate jets, the industry’s real output is overstated when its nominal sales are deflated with a general price index. The paper suggests that an industry-specific price index allows more accurate analyses of real economic activity of an industry. The methodology used in this paper could be useful for other industries where product price movements vary significantly from the changes in the general price level. JEL Classification L160,L620     

下一代通信网络中基于策略机制的无线资源管理

下一代无线通信系统是一种异构的网络体系，集成多种无线接入技术（Radio Access Technology，RAT）的同时提供多种窄带和宽带多媒体业务。这样的网络环境需要先进的RRM方法来处理复杂多变的无线信道、网络资源的动态配置及保障不同特征业务的服务质量（QoS），给无线资源管理（Radio Resource Management，RRM）带来了巨大的技术挑战。本文通过引入对网络进行策略控制的思想，提出了一种基于策略机制的通用方法，致力于解决下一代异构（heterogeneous）网络中的无线资源管理。文中着重讨论了基于策略机制的网络接入控制、切换，以及基于策略机制的QoS管理，给出了各功能模块的工作原理和通信过程的分析与设计。     

Adaptive rational equilibrium with forward looking agents

In adaptive rational equilibrium dynamics (ARED) agents choose between a costly rational expectation forecast and a cheap naive forecast, and the fractions using each of the two strategies evolve over time and are endogenously coupled to the market equilibrium price dynamics. In this setting, agents are backward looking in the sense that strategy selection is based on experience measured by relative past realized profits. When the selection pressure to switch to the more profitable strategy is high, instability and complicated chaotic price fluctuations arise.
In this paper we investigate the ARED with forward looking agents, whose strategy selection is based upon expected profits. Our findings suggest that forward looking behavior dampens the amplitude of price fluctuations, but local instability of the steady state remains. The global dynamics depends upon how sophisticated the forward looking behavior is. With perfectly forward looking agents, prices converge to a stable 2-cycle, whereas with forward looking agents who are boundedly rational concerning their estimate of expected profits, small amplitude chaotic price fluctuations might arise.
We also establish an equivalence relationship between a heterogeneous agent model with switching of strategies and a representative agent framework, where the representative agent optimally chooses between the benefits of a high quality forecast and the associated information gathering costs. To an outside observer it is impossible to distinguish between the two.     

The long-run dynamics of product and process innovations for a multi-product monopolist

This paper introduces the dynamical framework which combines product and process innovations. The model contributes to the theoretical literature on innovations in two ways. First, it permits for the simultaneous dynamics of both types of innovations which is rarely considered in the literature. Second, the products being generated by the innovations are heterogeneous in their investment characteristics. This allows for the formation of the dynamic interdependency between both types of innovations. As a result, the steady-state levels of process innovations for each product are different and influence the dynamics of product innovations in turn.     

基于蚁群算法的飞机加油车辆调度问题研究

飞机加油是停机坪地面保障作业的重要环节,能否对飞机按时按量的完成加油作业的关键因素在于对飞机加油车辆的合理调度,因此对飞机加油车辆调度的研究是十分有意义的。本文首先对飞机加油车辆的类型、功能、行驶过程及其注意事项做了简单的介绍,然后根据车辆调度的基本模型对飞机加油车辆调度的模型进行了比较具体的描述,文章最后用蚁群算法对某机场3个小时内飞机油罐加油车辆行驶情况进行仿真计算,希望通过对该模型的仿真优化计算,为机场加油车辆运行提供一种可行优化算法。     

航空发动机空中起动供油特性分析

本文研究航空发动机空中因富油问题导致起动困难,在分析起动供油的基础上,设计了高空修正模块来补偿飞行高度对供油特性的影响。并通过模拟试验进行了比较和分析。结果表明方案可行,能够解决发动机空中起动时的富油状态问题。