Early warning indicators? The effect of consumer and investor sentiments on the restaurant industry

This study looks at the influence of cyclical fluctuations of the consumer confidence index (CCI) and the volatility index (VIX) as early-warning indicators of the variations in restaurant performance. The industry has traditionally focused on past data and on microeconomic influences to anticipate its future performance, a procedure that does not consider possible cyclical fluctuations in restaurant performance metrics. These fluctuations are driven by sentiments of consumers and investors. The study uses the cyclical component of the applied data, followed by unit root and cointegration testing, with subsequent application of the Limited Information Maximum Likelihood technique. The results show both indicators have an effect on restaurant performance, where VIX has an impact on the current, expected, and overall restaurant performance, while the CCI’s influence is only partial (current performance). Policy-makers and planners could benefit from anticipating features of indicators to assess and steer the future performance of the restaurant industry.     

我国纺织品出口对经济增长贡献的实证研究

出口贸易是影响经济增长的重要因素。本文采用1980-2004年的数据,描述了我国纺织品出口的特点,并借助协整模型实证研究了纺织品出口对经济增长的影响,指出二者之间存在长期的动态关系。通过定量分析,发现纺织品出口对经济增长的直接拉动度和贡献率都较低,这是因为我国纺织服装行业一方面受宏观环境影响,另一方面自身竞争优势不足。本文经过研究,形成了对我国纺织品出口与经济增长之间关系直观而清晰的认识,并为无配额时代我国纺织业发展的后续研究提供了参考。     

Land use optimization in watershed scale

Managing a watershed for satisfying the inhabitant's demand is a difficult task if one has to maintain a reasonable balance between usually conflicting environmental flows and demands. The solution to these complex issues requires the use of mathematical techniques to take into account conflicting objectives. Many optimization models exist for general management systems but there is a knowledge gap in linking practical problems with the optimum use of all land resources under conflicting demands in a watershed. In the present study, an optimization problem has been formulated for the Brimvand watershed, Iran, comprising ca. 9572 ha to find out the most suitable land allocation to different land uses, viz. orchard, irrigated farming, dry farming and rangeland targeting soil erosion minimization and benefit maximization.     

城市化与能源消费关系的动态计量分析——以陕西省电力消费为例

运用经济计量方法,实证了陕西省城市化与能源消费之间的动态相关性,并利用因素分解模型定量测算出陕西城市化对能源消费变动的贡献份额.结果表明,陕西省城市化与能源消费量之间存在协整关系.但这种长期均衡的短期调整幅度不大;现阶段城市化对陕西能源需求的贡献作用尚比较小.且呈现逐年下降的趋势.因此,能源需求不会成为制约陕西省城市化进程中的瓶颈.     

人民币实际汇率波动对中欧进出口贸易影响的实证研究

本文通过建立GARCH模型量度了人民币对欧元实际汇率的波动性,并运用协整检验模型、误差修正模型、脉冲响应函数和方差分解技术就人民币实际汇率变动对中国与欧元区之间进出口贸易的影响进行分析。分析结果表明,中国对欧元区出口在长期内随汇率波动而增加,而进口却随汇率波动而减少;在短期内汇率波动推动中国进口,抑制中国出口。人民币升值在长期内给双边出口均造成伤害,但对中国出口伤害更大;在短期内人民币贬值将对中国进出口均有推动作用。本文分析还表明,在长期内,中国对欧元区出口收入效应远远大于欧元区对华出口收入效应;在短期内,中国实际收入变动对欧元区出口表现负向冲击,而欧元区实际收入变动对中国出口表现为正向冲击。中国汇率制度改革对中国出口欧元区产生推动作用,对欧元区出口产生抑制作用,且前者大于后者。实际汇率水平及其波动性变化对欧元区对华出口变动的解释力高于中国实际收入水平变化的解释力,而对于中国对欧元区出口的变动,欧元区实际收入水平变动的解释力高于实际汇率水平及其波动性变化的解释力。     

Asymptotics for Autocovariances and Integrated Periodograms for Linear Processes Observed at Lower Frequencies

One of the most frequently used class of processes in time series analysis is the one of linear processes. For many statistical quantities, among them sample autocovariances and sample autocorrelations, central limit theorems are available in the literature. We investigate classical linear processes under a nonstandard observation pattern; namely, we assume that we are only able to observe the linear process at a lower frequency. It is shown that such observation pattern destroys the linear structure of the observations and leads to substantially different asymptotic results for standard statistical quantities. Central limit theorems are given for sample autocovariances and sample autocorrelations as well as more general integrated periodograms and ratio statistics. Moreover, for specific autoregressive processes, the possibilities to estimate the parameters of the underlying autoregression from lower frequency observations are addressed. Finally, we suggest for autoregressions of order 2 a valid bootstrap procedure. A small simulation study demonstrates the performance of the bootstrap proposal for finite sample size.     

改革开放以来影响广东省外贸出口因素的实证分析

本文分析了广东省外贸出口与进口、FDI、出口对象国的经济增长及人民币名义汇率等影响因素的长期均衡关系,然后分析了短期中广东省外贸出口量对各影响因素波动的反应。得出结论:长期中,广东省出口额与外国收入、进口额、人民币名义汇率之间存在着正相关关系,而短期内进口额和人民币名义汇率对出口影响较大。     

Regulated absolute ruin problem with interest structure and linear dividend barrier

The uncontrolled surplus of an insurance company is a classical risk model. Now the risk model includes three features, namely debit interest, short-term and long-term invested interest, and linear dividend barrier. In this paper, the PDMP method and martingales are used for solvency studies in the risk model under regulation of minimum cash requirement. The integro-differential equations are derived for the expected discounted dividends under absolute ruin. In the case of exponential claim amounts, explicit expressions are obtained, as well as the numerical illustrations and their economic interpretation.     

线性代数双语教学模式实现途径研究

分析了线性代数双语教学的必要性与可行性,探讨了适合我校的教学模式,给出了教学目标和评价方法。     

Excel与SPSS在线性回归预测中的比较分析

线性回归分析是经济管理与预测的一个重要的量化分析方法。分别运用Excel与SPSS对同一实际问题进行线性回归分析,得出两种软件在线性回归预测问题上各有其优势,在经济管理的实际应用中无论选择那种软件都要了解其功能和操作的特点,有助于对实际问题恰当而且正确地分析与预测。