1,310 research outputs found
Impact of information cost and switching of trading strategies in an artificial stock market
This paper studies the switching of trading strategies and its effect on the
market volatility in a continuous double auction market. We describe the
behavior when some uninformed agents, who we call switchers, decide whether or
not to pay for information before they trade. By paying for the information
they behave as informed traders. First we verify that our model is able to
reproduce some of the stylized facts in real financial markets. Next we
consider the relationship between switching and the market volatility under
different structures of investors. We find that there exists a positive
relationship between the market volatility and the percentage of switchers. We
therefore conclude that the switchers are a destabilizing factor in the market.
However, for a given fixed percentage of switchers, the proportion of switchers
that decide to buy information at a given moment of time is negatively related
to the current market volatility. In other words, if more agents pay for
information to know the fundamental value at some time, the market volatility
will be lower. This is because the market price is closer to the fundamental
value due to information diffusion between switchers.Comment: 15 pages, 9 figures, Physica A, 201
Evaluating Feynman integrals by the hypergeometry
The hypergeometric function method naturally provides the analytic
expressions of scalar integrals from concerned Feynman diagrams in some
connected regions of independent kinematic variables, also presents the systems
of homogeneous linear partial differential equations satisfied by the
corresponding scalar integrals. Taking examples of the one-loop and
massless functions, as well as the scalar integrals of two-loop vacuum
and sunset diagrams, we verify our expressions coinciding with the well-known
results of literatures. Based on the multiple hypergeometric functions of
independent kinematic variables, the systems of homogeneous linear partial
differential equations satisfied by the mentioned scalar integrals are
established. Using the calculus of variations, one recognizes the system of
linear partial differential equations as stationary conditions of a functional
under some given restrictions, which is the cornerstone to perform the
continuation of the scalar integrals to whole kinematic domains numerically
with the finite element methods. In principle this method can be used to
evaluate the scalar integrals of any Feynman diagrams.Comment: 39 pages, including 2 ps figure
Settlement prediction model of slurry suspension based on sedimentation rate attenuation
AbstractThis paper introduces a slurry suspension settlement prediction model for cohesive sediment in a still water environment. With no sediment input and a still water environment condition, control forces between settling particles are significantly different in the process of sedimentation rate attenuation, and the settlement process includes the free sedimentation stage, the log-linear attenuation stage, and the stable consolidation stage according to sedimentation rate attenuation. Settlement equations for sedimentation height and time were established based on sedimentation rate attenuation properties of different sedimentation stages. Finally, a slurry suspension settlement prediction model based on slurry parameters was set up with a foundation being that the model parameters were determined by the basic parameters of slurry. The results of the settlement prediction model show good agreement with those of the settlement column experiment and reflect the main characteristics of cohesive sediment. The model can be applied to the prediction of cohesive soil settlement in still water environments
Grand Unified Yukawa Matrix Ansatz: The Standard Model Fermion Mass, Quark Mixing and CP Violation Parameters
We propose a new mass matrix ansatz: At the grand unified (GU) scale, the
standard model (SM) Yukawa coupling matrix elements are integer powers of the
square root of the GU gauge coupling constant \varepsilon \equiv
\sqrt{\alpha_{\text{GU}}}, multiplied by order unity random complex numbers. It
relates the hierarchy of the SM ermion masses and quark mixings to the gauge
coupling constants, greatly reducing the SM parameters, and can give good
fitting results of the SM fermion mass, quark mixing and CP violation
parameters. This is a neat but very effective ansatz.Comment: 4 pages (two columns), by REVTeX 4, 2 tables, no figures, version for
publication in CP
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