能源强度变动的多因素分解方法研究

为更加全面、准确地度量影响能源强度变动的因素,在分析相关研究文献的基础上,提出包含产业结构份额、部门能源效率份额和能源结构份额的三因素几何均值能源强度分解模型,该模型不仅能够将能源消费结构对能源强度的影响从产业结构和部门效率份额中分离出来,而且克服了当数据集合中出现零值时,现有处理方法产生较大误差的缺点,提供了一种精度较高的多因素能源强度分解方法.     

技术创新影响因素的区域差异:以中国30个省份为例的研究

利用中国30个省(直辖市、自治区)的面板数据,对中国技术创新影响因素的区域差异进行了实证分析,不仅研究了地区研发投入对技术创新的影响,还考虑了财政创新支持、金融创新支持、外商投资的技术溢出、地区经济的转轨情况、地区人力资本禀赋等因素的影响作用.实证结果表明,研发投入是地区技术创新的主要推动因素,各个因素对技术创新影响的区域差异明显.     

不完全信息下基于价格信号的投资博奕模型

在金融市场中,投资者的预期是决定市场走向的重要因素,而机构投资者的资源禀赋与其市场操纵行为的获利之间往往呈现正相关关系.通过描述机构和散户基于价格信号传递的对策过程,建立了一个博弈模型,模型演绎结果在理论上证实了上述经济现实.     

Nonlinear dynamics in a heterogeneous duopoly game with adjusting players and diseconomies of scale

A repeated, discrete time, heterogeneous Cournot duopoly game with bounded rational and adaptive players adjusting the quantities of production is subject of investigation. Linear inverse demand function and quadratic cost functions reflecting decreasing returns to scale are assumed. The game is modeled with a system of two difference equations. Evolution of outputs over time is obtained by iteration of a two dimensional nonlinear map. Existing equilibria and their stability are analyzed. In face of diseconomies of scale, bounded rational and adaptive duopolists are shown to experience a decrease in the latitude of their output adjustment decisions with respect to the market stability compared to constant returns to scale and ceteris paribus. Chaotic dynamics is confirmed to depend mainly on the adjustment behavior of the bounded rational player, who if overshoots leaves the adaptive player with limited opportunities to stabilize the market again, hence industries facing diseconomies of scale are found to be less stable than those with constant marginal costs. Complexity of the dynamical system is examined by means of numerical simulations, where the paper extends the results of other authors who considered analogous games assuming linear cost functions. Intermittent transition to chaos and attractor merging crisis are shown among others.     

Reliable amplitude and frequency estimation for biased and noisy signals

Robust estimation of the amplitude, frequency and bias of unknown noisy sinusoidal signals is considered in this paper. It is only assumed that the measurements noise is bounded without any additional information such as stationarity, uncorrelation or type of distribution. In this context, the aim is to compute the set of all admissible values that are consistent with the measurements and with the error bound. The estimation problem is formulated as a Constraint Satisfaction Problem (CSP) where the amplitude, frequency and bias constitute the variables and a function relating them to the output is the constraint. Interval constraint propagation techniques are used to solve, in a guaranteed way, this problem. In order to illustrate the principle and the efficiency of the approach, numerical simulations are provided.     

Measuring polarization in preferences

In this paper, we study the measurement of polarization in collective decision making problems with ordinal preferences over alternatives. We argue that polarization can be measured as an aggregation of antagonisms over pairs of alternatives in the society. We propose a measure of this sort and show that it is the only measure satisfying some normatively appealing conditions.     

Mean–variance efficiency of DC pension plan under stochastic interest rate and mean-reverting returns

This paper studies the optimization problem of DC pension plan under mean–variance criterion. The financial market consists of cash, bond and stock. Similar to Guan and Liang (2014), we assume that the instantaneous interest rate is an affine process including the Cox–Ingersoll–Ross (CIR) model and Vasicek model. However, we assume that the expected return of the stock follows a completely different mean-reverting process, which can well display the bear and bull features of the market, and the market price of the stock index is the Ornstein–Uhlenbeck process. The pension manager thus has to undertake the risks of interest rate and market price of stock index. Besides, a special stochastic contribution rate is formulated. The goal of the pension manager is to maximize the expected terminal value and minimize the variance of terminal value. We will use the technique developed by Guan and Liang (2014) to tackle this problem and derive the closed-forms of efficient frontier and strategies. Numerical analysis is given in the end of this paper to show the economic behavior of the efficient frontier and strategies.     

具周期系数的单种群模型及其最优捕获策略

该文用一种新的方法, 讨论了单种群生物资源的捕获优化问题.以最大的可持续单位时间捕获量为管理目标, 得到一类非自治单种群捕获模型的最优捕获策略, 所得结果包括了文献中研究过的几乎所有单种群捕获模型的相应研究结果.     

Approaching human language with complex networks

The interest in modeling and analyzing human language with complex networks is on the rise in recent years and a considerable body of research in this area has already been accumulated. We survey three major lines of linguistic research from the complex network approach: 1) characterization of human language as a multi-level system with complex network analysis; 2) linguistic typological research with the application of linguistic networks and their quantitative measures; and 3) relationships between the system-level complexity of human language (determined by the topology of linguistic networks) and microscopic linguistic (e.g., syntactic) features (as the traditional concern of linguistics). We show that the models and quantitative tools of complex networks, when exploited properly, can constitute an operational methodology for linguistic inquiry, which contributes to the understanding of human language and the development of linguistics. We conclude our review with suggestions for future linguistic research from the complex network approach: 1) relationships between the system-level complexity of human language and microscopic linguistic features; 2) expansion of research scope from the global properties to other levels of granularity of linguistic networks; and 3) combination of linguistic network analysis with other quantitative studies of language (such as quantitative linguistics).