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991.

Who does the law treat as a “consumer” and why does it matter? How should China’s notion of a “consumer” best be articulated within the law and applied in practice? This article will attempt to answer these intriguing questions by first focusing on the approach taken to define a “consumer” in China’s Law on the Protection of Consumer Rights and Interests before examining the legal notion of a “consumer” in comparative perspective, in order to further understand the competing rationales behind the consumer protection law. This article will explore this Chinese definition of a “consumer” to propose how China’s vague and unworkable statutory definition of a ‘consumer’ should be amended in future.

  相似文献   
992.
Journal of Business Ethics - By synthesizing the argumentation theory of new rhetoric with research on heuristics and motivated reasoning, we develop a conceptual view of argumentation based on...  相似文献   
993.
Knoblock and Korf have determined that abstraction can reduce search at a single agent from exponential to linear complexity (Knoblock 1991; Korf 1987). We extend their results by showing how concurrent problem solving among multiple agents using abstraction can further reduce search to logarithmic complexity. We empirically validate our formal analysis by showing that it correctly predicts performance for the Towers of Hanoi problem (which meets all of the assumptions of the analysis). Furthermore, a powerful form of abstraction for large multiagent systems is to group agents into teams, and teams of agents into larger teams, to form an organizational pyramid. We apply our analysis to such an organization of agents and demonstrate the results in a delivery task domain. Our predictions about abstraction's benefits can also be met in this more realistic domain, even though assumptions made in our analysis are violated. Our analytical results thus hold the promise for explaining in general terms many experimental observations made in specific distributed AI systems, and we demonstrate this ability with examples from prior research.This research has been sponsored, in part, by the National Science Foundation under grants IRI-9015423 and IRI-9010645, by the University of Michigan Rackham Graduate School, and by a Bell Northern Research Postgraduate Award.  相似文献   
994.
In the current essay, the author draws on his experience as a serving member of the Armed Forces to discuss the problem of developing military leaders capable of mitigating the disruptive nature of war. Specifically, it discusses the staff ride, a comprehensive analysis of historical events conducted through observation, reflection, and discussion, to develop in leaders an understanding that nothing ever works out the way a leader intends or expects. For the military leader facing the uncertainty and ambiguity of modern combat, this lesson from history is arguably the most essential.  相似文献   
995.
996.
This study analyzes the effect of premium rates on banks’ incentives to join a deposit insurance scheme and their incentives to invest in risky projects under a voluntary deposit insurance scheme. We find that in order to maximize social welfare, the insurance agency must either set the premium rate to be low so as to attract all banks to join the insurance scheme, or not to have the deposit insurance at all. However, the low premium rate in the voluntary scheme does not balance the budget of the deposit insurance. We also show that in the compulsory deposit insurance scheme, however, it is possible to impose an optimal premium rate that can balance the insurance agency’s budget and achieve the highest social welfare. The results also present the dominance of the compulsory scheme over the voluntary scheme in terms of maximizing social welfare and balancing the budget.
Min-Teh Yu (Corresponding author)Email:
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997.
A robust VaR model under different time periods and weighting schemes   总被引:1,自引:1,他引:0  
This paper analyses several volatility models by examining their ability to forecast Value-at-Risk (VaR) for two different time periods and two capitalization weighting schemes. Specifically, VaR is calculated for large and small capitalization stocks, based on Dow Jones (DJ) Euro Stoxx indices and is modeled for long and short trading positions by using non parametric, semi parametric and parametric methods. In order to choose one model among the various forecasting methods, a two-stage backtesting procedure is implemented. In the first stage the unconditional coverage test is used to examine the statistical accuracy of the models. In the second stage a loss function is applied to investigate whether the differences between the models, that calculated accurately the VaR, are statistically significant. Under this framework, the combination of a parametric model with the historical simulation produced robust results across the sample periods, market capitalization schemes, trading positions and confidence levels and therefore there is a risk measure that is reliable.
Stavros DegiannakisEmail:
  相似文献   
998.
This paper investigates the role of stochastic volatility and return jumps in reproducing the volatility dynamics and the shape characteristics of the Korean Composite Stock Price Index (KOSPI) 200 returns distribution. Using efficient method of moments and reprojection analysis, we find that stochastic volatility models, both with and without return jumps, capture return dynamics surprisingly well. The stochastic volatility model without return jumps, however, cannot fully reproduce the conditional kurtosis implied by the data. Return jumps successfully complement this gap. We also find that return jumps are essential in capturing the volatility smirk effects observed in short-term options.
Sol KimEmail:
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999.
This paper proposes an extension of the minimal Hellinger martingale measure (MHM hereafter) concept to any order q≠1 and to the general semimartingale framework. This extension allows us to provide a unified formulation for many optimal martingale measures, including the minimal martingale measure of Föllmer and Schweizer (here q=2). Under some mild conditions of integrability and the absence of arbitrage, we show the existence of the MHM measure of order q and describe it explicitly in terms of pointwise equations in ? d . Applications to the maximization of expected power utility at stopping times are given. We prove that, for an agent to be indifferent with respect to the liquidation time of her assets (which is the market’s exit time, supposed to be a stopping time, not any general random time), she is forced to consider a habit formation utility function instead of the original utility, or equivalently she is forced to consider a time-separable preference with a stochastic discount factor.  相似文献   
1000.
The literature has suggested that earnings and earnings forecasts provide stronger signals than dividends about future performance of a firm. We test the information effects of simultaneous announcement of earnings and dividends in the Hong Kong market, distinguished by three interesting features (concentrated family-shareholdings, low corporate transparency, and no tax on dividends). Our results show significant share price reactions to unexpected earnings and dividend changes, but dividends appear to play a dominant role over earnings in pricing, a result contrary to findings in the literature. The signaling hypothesis works primarily for firms with earning increases, while the maturity hypothesis works mainly for firms with earnings declines.
Tak Yan LeungEmail:
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