Determination of Discrete Spectrum in a Random Field

We consider a two dimensional frequency model in a random field, which can be used to model textures and also has wide applications in Statistical Signal Processing. First we consider the usual least squares estimators and obtain the consistency and the asymptotic distribution of the least squares estimators. Next we consider an estimator, which can be obtained by maximizing the periodogram function. It is observed that the least squares estimators and the estimators obtained by maximizing the periodogram function are asymptotically equivalent. Some numerical experiments are performed to see how the results work for finite samples. We apply our results on simulated textures to observe how the different estimators perform in estimating the true textures from a noisy data.     

强自然垄断定价理论与中国电价规制制度分析

强自然垄断行业由于其定价方面的两难困境 ,需要规制者对其产品定价进行规制以在厂商利润与社会福利之间进行权衡。边际成本定价原则并不适合于自然垄断厂商。本文在规制定价理论以及激励规制理论的基础上 ,对中国电力定价问题进行了分析 ,认为电价改革的第一步应在发电环节中引入竞争的基础上 ,对不同效率类型的电力厂商设计不同激励强度的定价机制 ,另外本文尝试着对不同技术效率的电力厂商列出了不同激励强度的价格规制方案菜单     

强势美元政策：有效性检讨与可持续性分析

强势美元政策保证了外资对美国的强劲流入,支撑了美国的低通货膨胀,弥补了美国的储蓄———投资缺口和对外贸易逆差,巩固了美元的全球霸权地位,总之,强势美元政策促进了美国的经济增长。由于美国存在对强势美元政策的依赖性及美元的全球霸权地位没有受到实质性的挑战,在可预见的将来,强势美元政策仍会持续也仍可持续,美国仍将实行强势美元政策。     

‘Agents-in-focus’ and ‘Agents-in-context’: The strong structuration analysis of central government accounting practices and reforms in Nepal

Drawing on Stones’ (2005) strong structuration theory, the paper unfolds why and how the key stakeholders of central government accounting in Nepal are involved in the reproduction of routinised accounting practices, resisting the externally-propagated changes. Government accountants (the agents-in-focus) through their capability to control the budget routines have enjoyed a powerful social position in their position–practice relations with the agents-in-context, i.e. professional accountants and international consultants, higher-level officers and administrators, auditors, and politicians. Social position along with historically-imbued dispositions and their conduct and context analysis have enabled government accountants to strategically exercise their agency. Government accountants have articulated duality and a dialectic relation with the agents-in-context, which have resulted in the reproduction of everyday accounting practice and the resistance to the World Bank-led reforms, such as accrual accounting and, more recently, the Cash-Basis IPSAS.     

Strong Nash equilibrium in games with common and complementary local utilities

A rather general class of strategic games is described where the coalitional improvements are acyclic and hence strong Nash equilibria exist: The players derive their utilities from the use of certain facilities; all players using a facility extract the same amount of local utility therefrom, which amount depends both on the set of users and on their actions, and is decreasing in the set of users; the ultimate utility of each player is the minimum of the local utilities at all relevant facilities. Two important subclasses are “games with structured utilities,” basic properties of which were discovered in 1970s and 1980s, and “bottleneck congestion games,” which attracted researchers’ attention quite recently. The former games are representative in the sense that every game from the whole class is isomorphic to one of them. The necessity of the minimum aggregation for the existence of strong Nash equilibria, actually, just Pareto optimal Nash equilibria, in all games of this type is established.     

Coalition formation in general apex games under monotonic power indices

An apex game consists of one apex player and a set of minor players. We identify two key properties of apex games and use them to introduce the class of general apex games. We derive players' preferences over winning coalitions by applying strongly monotonic power indices on such a game and all its subgames and investigate whether there are core stable coalitions in the induced hedonic coalition formation game. Besides several general results, in particular, we develop conditions on the game for the Shapley–Shubik index, the Banzhaf index, and the normalized Banzhaf index.     

How to inhibit a partner's strong and weak forms of opportunism: Impacts of network embeddedness and bilateral TSIs

This study investigates the moderating effects of a firm's network embeddedness and a partner's transactional specific investments (TSIs) on relationships between the firm's TSIs and its partner's strong- and weak-form opportunism, and compares the efficiency among these moderator variables. The regression results suggest that (1) a firm's TSIs are positively related to partner's opportunism when network embeddedness and the partner's TSIs are relatively low; but (2) a firm's TSIs are negatively related to partner's opportunism when network embeddedness and the partner's TSIs are relatively high. Furthermore (3) network embeddedness is more effective in inhibiting partner's weak-form opportunism than in inhibiting strong-form opportunism resulting from the firm's TSIs. Finally (4) with regard to the relationship between TSIs and weak-form opportunism, the negative moderating effect of network embeddedness is greater than the negative moderating effect of partner's TSIs. This study explains reasons why conflicting views exist about the relationship between TSIs and partner's opportunism, reveals the differences in the moderating effects of network embeddedness and partner's TSIs, and makes new contributions to both transaction cost theory and embeddedness literature. It also provides, for firms involved in TSIs in a buyer–supplier relationship, insightful managerial suggestions about ways to reduce their partner's varying forms of opportunism.     

Analyzing the global human appropriation of net primary production — processes, trajectories, implications. An introduction

Humanity's role in shaping patterns and processes in the terrestrial biosphere is large and growing. Most of the earth's fertile land is used more or less intensively by humans for resource extraction, production, transport, consumption and waste deposition or as living space. Biomass production on cropland, grazing areas and in managed forests dominates area requirements, but other processes such as soil degradation, human-induced fires and expansion of settlements and infrastructure play an increasingly important role as well. The growing human domination of terrestrial ecosystems contributes to biodiversity loss as well as to a reduced capability of ecosystems to deliver vital services such as buffering capacity, soil conservation or self-regulation. This special section is devoted to the presentation of recent research into the patterns, determinants and implications of the human appropriation of net primary production (HANPP), an integrated socio-ecological indicator of land use intensity. By measuring the combined effect of land conversion and biomass harvest on the availability of trophic energy (biomass) in ecosystems, HANPP explicitly links natural with socioeconomic processes and allows for integrated analyses of land systems. This introductory article explains the rationale that links current HANPP research to Ecological Economics and discusses issues of definition and methods shared by all articles included in the special section. Finally, it gives an overview of the individual papers, provides some general conclusions and presents an outlook for future research: a better understanding of long-term trajectories of HANPP, of the significance of trade patterns as well as of the future role of bioenergy are highlighted as important issues to be addressed in the coming years.     

中国股票市场有效性实证分析

股票市场的有效性直接影响资金配置的效率,中国股市的有效性问题一直是业界讨论的焦点,其有效性的检验主要集中在市场是否具有弱式有效方面。本文依据Fama对股票市场的定义及三个层次市场对应的有效市场检验方法,对国内股市的有效性进行检验。首先使用沪、深两市日收益率数据,对各自日收益率之间的相关性进行检验,发现日收益率之间不存在自相关和偏自相关,由此认为中国股票市场弱式有效。然后采用事件研究法,以年报公布作为事件,以年报公布日前、后共30日,120支股票收益率数据为样本,对我国股票市场半强式有效性进行检验,结果发现年报公布日前、后超额收益存在明显变化,以此认为中国股市目前不符合半强有效市场的定义。最后对市场中存在的问题进行了分析,并给出了政策建议。     

市场转型、社会资本与求职行为——关于大学生求职的个案研究

市场转型过程中,大学生的就业体现出就业模式市场化,分配主体多元化,就业形势严峻化。以往研究较多关注社会资本对求职的具体作用,而忽略社会资本运作的深层问题探讨。通过个案调查认为,社会关系网络是求职的重要机制,强关系、弱关系在求职中都可能提供信息和影响,市场因素的介入引起＂差序格局＂变迁,物质性交易是弱关系提供影响的维系力,强关系和弱关系将在完善的制度环境中共同充当信息桥的角色。