Some problems with transient phenomena when simulating unpaced lines

Unlike earlier simulation studies of unpaced production lines which generally concentrated on steady-state behavior, we are concerned with their transient characteristics. This paper (1) presents an approach for studying and monitoring transient behavior, (2) reports some important transient operating characteristics previously overlooked, and (3) demonstrates that the conflicting results reported in some of the earlier simulation studies are due to an inadequate accounting for transient behavior. Thus, this paper illustrates the importance of having a better understanding of transient behavior in unpaced lines, and presents our initial steps towards dealing with it.     

The Relevance of the Group for the Evolution of Social Norms and Values

Social group selection is explored as a scheme for the evolution of institutions giving rise to coordination and cooperation. Its crucial characteristic is the formation of psychic ties between group members which further the compliance with institutions by causing individuals to systematically underrate both the benefits of rule-breaking and the costs of rule-enforcement. With regard to the relationship between groups, these ties allow for the evolution of cooperation by enhancing selective forces acting between groups over those acting within. The resulting set of institutions represents a spontaneous order since neither perfect knowledge nor goodwill of any actor are required.     

领先财富管理的运营思路——BCG中国财富管理市场研究报告摘要

波士顿咨询公司(BCG)发布的有关中国财富管理市场的最新报告探讨了在中国建立领先的财富管理业务的关键因素.BCG授权本刊撷取其精要,希望能给予致力于提升中国财富管理水平的机构和理财从业人员有益的启示.     

The risk return tradeoff in the long run: 1836–2003

Previous studies typically find a statistically insignificant relation between the market risk premium and its expected volatility. Further, several of these studies estimate a negative risk return tradeoff, contrary to the predictions of mainstream theory. Using simulations, I demonstrate that even 100 years of data constitute a small sample that may easily lead to this finding even though the true risk return tradeoff is positive. Small-sample inference is plagued by the fact that conditional volatility has almost no explanatory power for realized returns. Using the nearly two century history of U.S. equity market returns from Schwert [1990. Indexes of United States stock prices from 1802 to 1987. Journal of Business 63, 399–426], I estimate a positive and statistically significant risk return tradeoff. Finally, exploratory analysis suggests a role for a time-varying relation linked to the changing nature of the U.S. economy.     

The Adjustment Property

An input–output (IO) system which is capable of producing any semi-positive net product by an adequate choice of the activity levels of its processes satisfies the ‘adjustment’ property. We analyze under which conditions the adjustment property holds for IO systems in which some produced goods have a purely intermediate character. The peculiarity of these pure capital goods is that final demand for them is identically zero. One of the ways to deal with this type of system is to eliminate the pure capital goods, by means of vertical integration.     

Around and Around: The Expectations Hypothesis

We show how to construct models of the term structure of interest rates in which the expectations hypothesis holds. McCulloch (1993) presents such a model, thereby contradicting an assertion by Cox, Ingersoll, and Ross (1981), but his example is Gaussian and falls outside the class of finite-dimensional Markovian models. We generalize McCulloch's model in three ways: (i) We provide an arbitrage-free characterization of the unbiased expectations hypothesis in terms of forward rates; (ii) we extend this characterization to a whole class of expectations hypotheses; and (iii) we show how to construct finite-dimensional Markovian and non-Gaussian examples.