829 research outputs found
Relative Distress and Return Distribution Characteristics of Japanese Stocks, a Fuzzy-Probabilistic Approach
In this article, we demonstrate that a direct relation exists between the context of Japanese firms indicating relative distress and conditional return distribution properties. We map cross-sectional vectors with company characteristics on vectors with return feature vectors, using a fuzzy identification technique called Competitive Exception Learning Algorithm (CELA)1. In this study we use company characteristics that follow from capital structure theory and we relate the recognized conditional return properties to this theory. Using the rules identified by this mapping procedure this approachenables us to make conditional predictions regarding the probability of a stock's or a group of stocks' return series for different return distribution classes (actually return indices). Using these findings, one may construct conditional indices that may serve as benchmarks. These would be particularly useful for tracking and portfolio management.capital structure;asset pricing;fuzzy systems;conditional return distribution;heuristic learning
Impact of Japanese Mergers on Shareholder Wealth: An Analysis of Bidder and Target Companies
The market for corporate control in the second largest economy in the world behaves very different from that in the U.S. Using a sample of 91 mergers in the period 1982-2003 we document several distinctive features of this market in Japan. First, we show that in stark contrast to the pro-cyclical U.S. merger waves, mergers in Japan tend to be counter-cyclical, both with respect to the general economy as well as with respect to stock market valuations. Second, and again in contrast to the U.S. experience, we find that a significant fraction of Japanese mergers are orchestrated by the main banks; in such cases, mergers are not between two weak companies, but at least one of the merging companies is financially strong. Other distinctive features of Japanese mergers are the positive pre-announcement returns accruing to both bidders and targets, with bidders capturing approximately half the gains that accrue to target firms. We also find differential shareholder wealth effects in the bubble period (1982-1989), the early 1990s, and the post-financial regulation regime (1997-2003). Overall our results point to a market for corporate control that is distinctly less shareholder-centered than that in the U.S. and one where creditors play an important, perhaps dominant, role.mergers;Japanse mergers;corporate control;take-over
Competition and group size in Thomas's langurs ( Presbytis thomasi): the folivore paradox revisited
Abstract Among primates, group size is highly variable.
The standard ecological model assumes that better
predation avoidance as group size increases favours living
in larger groups, whereas increased travel costs and
reduced net food intake due to within-group competition
for resources set the upper limit. Folivorous primates,
however, tend to defy this generalisation in that some
live in small groups despite low costs of feeding competition.
To resolve this folivore paradox , it has been suggested
that folivore group size is limited by social factors
such as male harassment or infanticide, or that females
can disperse more easily and thus maintain group size
near optimum levels. In this paper, we examine the effects
of group size on home range size, day-journey
length, activity budget and diet in wild Thomas's langurs
(Presbytis thomasi), which live in one-male multi-female
groups with a limited life cycle. We examined only data
from the stable middle tenure phase when factors such as
the strength of the breeding male or the way in which
groups were formed did not influence ranging and activities.
During this phase, group size affected day-journey
length and home range size, and had a minor effect on
diet, but did not influence time spent feeding or resting,
allogrooming or birth rates. Hence the upper limit to
group size during the middle tenure phase in Thomas s
langurs is not set by feeding competition. The folivore
paradox is not due to frequent female dispersal in
Thomas s langurs. The timing of female dispersal is not
as expected if it serves to keep group sizes near the ecological
optimum, and groups seem to be below this optimum.
Instead, female reproductive success is presumpresumably
maximised in small to mid-sized groups because
larger groups show a clear trend to experience higher
risk of take-over, often accompanied by infanticide. Because
females can redistribute themselves among nearby
groups when groups reorganise each time a new male
starts up a new group, females can keep the group small.
Thus, a social factor, risk of infanticide, seems to provide
the selective advantage to small group size in
Thomas s langurs
Using the Dynamics of a Person-Context System to Describe Childrenâs Understanding of Air Pressure
Education and development as complex dynamic agent systems::how theory informs methodology
This chapter argues that the integrative theory that can serve as the basis of integrative methodology is the theory of complex dynamic agent systems. It explains this general theory by focusing on teachingâlearning processes in the educational context, and on pedagogical actions and dynamic assessment in the classroom. A complex dynamic system can be defined as a network of components that interact with each other. Self-organization means that the network of components organizes itself into a particular pattern of temporarily self-sustaining relationships among components. âSelf-sustainingâ means that systems resist external perturbations, at least to a certain extent. External perturbations, when they occur, may function for the better or for the worse. Emergence means that the interactions between the components of a system lead to the origination of properties that are new, in the sense that they transcend the properties of the components taken separately
The Socially Situated Dynamics of Childrenâs Learning Processes in Classrooms:What Do We Learn from a Complex Dynamic Systems Approach?
This article concentrates on the question what kind of model-conceptual and statistical -can serve as a good working model for the study of learning and teaching processes qua processes. We claim that a good way of answering this question is to begin by observing a teaching and learning process as, where, and when it occurs. In addition, a conceptual model of intertwined learning-teaching processes is discussed, and dynamic modeling as an approach to theory formation about teaching-learning processes. The focus lies on the evolution term, the timescale of interaction processes, state space as a perspective on teacher-student interaction dynamics, and the principle of agency. Finally, an empirical approach to studying teaching-learning processes is illustrated by means of a case study, focusing on the use of cluster analyses techniques. In the Conclusion and Discussion section, further perspectives on theory building and empirical research are discussed
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