Fractional integration in daily stock market indices at Jordan's Amman stock exchange

Using daily data on five sectoral indices from 2006 to 2014, this paper aims to investigate the possibility of fractional integration in sectoral returns (and their volatility measures) at Jordan's Amman stock exchange (ASE). Empirical analysis, using the log-periodogram (LP) and local whittle (LW) based semi-parametric fractional differencing techniques suggest that all sectoral returns at ASE exhibit short memory. However, in the case of volatility measures, we found evidence of long memory. Following the recent literature that argues that structural breaks in a time series could also explain the presence of long memory, we tested the volatility measures for the presence of structural breaks. We found that long memory in some volatility measures could be attributed to the presence of structural breaks. Furthermore, using impulse response functions (IRF) based on ARFIMA, we found that shocks to sectoral returns at ASE exhibit short run persistence, whereas shocks to volatility measures display long run persistence.     

Criteria for the Stochastic Ordering of Random Sums,with Actuarial Applications

It is shown that vectors ( S M 1 , … , S Mn ) and ( S' M'1 , …, S' M'n ) of random sums of positive random variables are stochastically ordered by upper orthant dependence, lower orthant dependence, concordance or by the supermodular ordering whenever their corresponding random numbers of terms ( M 1 , … , M n ) and ( M' 1 , … , M' n ) are themselves ordered in this fashion. Actuarial applications of these results are given to different dependence structures for the collective risk model with several classes of business.     

由广告引发的艺术思考

由广告是不是一门艺术的争议出发,探讨了艺术与功利之间的关系。通过思考分析,得出广告应该属于艺术门类的结论。     

Trade,money and employment in intertemporal optimizing models of growth

This paper unites elements of Sidrauski's (1967) monetary model of growth, Ventura's (1997) analysis of the effects of international trade on growth, and some work on the labour market implications of growth by Barro and Sala-i-Martin (1995). It was shown by Ventura that, for a small economy, free international trade leads to an increase of the de facto elasticity of substitution between the domestic factors of production. The first part of the paper analyses how such an increase in the elasticity of substitution influences the steady state and the speed of convergence. From the Sidrauski model we know that money is super-neutral in the long-run but that monetary policy can have real effects along the transition path as long as the intertemporal elasticity of substitution is not equal to one. In the second part of this paper, it is shown how these results also depend on the elasticity of substitution between factors of production. The results give some important insights into possible interactions between monetary and trade policy in the long and short run. The last part of the paper deals with a modified version of the monetary growth model, which includes endogenous labour supply as in Klump (1993) or Barro and Sala-i-Martin (1995). In this context, international trade, by increasing the elasticity of substitution, leads to lower domestic employment in the long run whereas monetary policy may be able to increase employment at least in the short run. Thus, under certain circumstances, trade and monetary policy can be regarded as complementary with respect to their labour market effects.     

征信体系的作用与效率——基于信息不对称随机有限重复博弈的分析

征信体系的意义可以用重复博弈理论来加以解释.本文建立了一个信息不对称随机有限重复信用博弈模型,证明如果存在征信体系实现的信息共享机制,那么不论借款者的类型是什么,诚实守信是可以作为序列均衡的结果在有限重复博弈的绝大多数时期中出现的.如果不存在信息共享机制,信贷市场有可能消失,即便引入资产抵押,信贷市场仍是不完全的.基于上述序列均衡分析,本文进一步阐释了全面征信、法律保障、市场结构对征信体系效率运行的重要性.就发展中国家而言,成立中性、独立、信息全面的国家信用局和鼓励民营信用公司积极竞争,完善义务征信的法律体系是较为理想和可行的选择     

Two-Sided Bounds for Ruin Probabilities when the Adjustment Coefficient does not Exist

In this paper, we derive two-sided bounds for the ruin probability in the compound Poisson risk model when the adjustment coefficient of the individual claim size distribution does not exist. These bounds also apply directly to the tails of compound geometric distributions. The upper bound is tighter than that of Dickson (1994). The corresponding lower bound, which holds under the same conditions, is tighter than that of De Vylder and Goovaerts (1984). Even when the adjustment coefficient exists, the upper bound is, in some cases, tighter than Lundberg's bound. These bounds are applicable for any positive distribution function with a finite mean. Examples are given and numerical comparisons with asymptotic formulae for the ruin probability are also considered.     

U.S. Virgin Islands National Park:

No abstract available for this article.     

Perfectly competitive bilateral exchange without discounting

In a random-matching economy of traders who maximize cumulative consumption (overtaking criterion), the stationary, Markov, Bayesian-perfect equilibrium is studied. At such equilibrium, two results hold: (1) perfect substitutability between current and future consumption implies a no-surplus condition; and (2) by the no-surplus condition, there is a nominal price at which all trades must occur. These results strengthen the seminal results of Ostroy (1973) regarding monetary bilateral exchange in two ways: the incentive compatibility of the equilibrium trading pattern is established and a less roundabout trading pattern enhances welfare by enabling consumption to occur more frequently.     

The involvement of utilities in the development of broadband infrastructure: A comparison of EU case studies

Energy companies and other utility providers have been often involved in the provision of telecommunications services. Nevertheless, their contribution to broadband development has varied significantly over time. In the late 1990s, both local and national utilities in the European Union (EU) engaged in the provision of broadband networks, but only few of them managed to establish themselves as major broadband providers. More recently, new projects involving national utilities have been announced in several EU countries, opening new scenarios for utilities’ contribution to Next Generation Access (NGA) development. This paper identifies and explores the factors affecting the entry and the success of utilities in the EU broadband market, through the comparison of four case studies from four EU countries (Germany, Italy, Sweden and the UK). The evolution of utility involvement in the EU broadband markets is assessed against the interaction of market, technology and policy factors, focusing on the impact of policy and regulatory measures. As a result, this paper provides fruitful insights into the relevance and effectiveness of public interventions in broadband markets. Across the four case studies, public support and public ownership emerged as the main drivers for the involvement of utilities in EU broadband markets, with regulatory measures and economies of scope exerting a limited and decreasing influence. However, the contribution of utilities has varied significantly across the cases studied, reflecting the different approaches taken at national and local level to support broadband development, in spite of the common regulatory framework.