1,280 research outputs found
Guest Editorial: The Ethics of Reviewing
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67095/2/10.1177_00220345760550050201.pd
Hollywood blockbusters and long-tailed distributions: An empirical study of the popularity of movies
Numerical data for all movies released in theaters in the USA during the
period 1997-2003 are examined for the distribution of their popularity in terms
of (i) the number of weeks they spent in the Top 60 according to the weekend
earnings, and (ii) the box-office gross during the opening week, as well as,
the total duration for which they were shown in theaters. These distributions
show long tails where the most popular movies are located. Like the study of
Redner [S. Redner, Eur. Phys. J. B 4, 131 (1998)] on the distribution of
citations to individual papers, our results are consistent with a power-law
dependence of the rank distribution of gross revenues for the most popular
movies with a exponent close to -1/2.Comment: 4 pages, 4 figure
Multiple Tipping Points and Optimal Repairing in Interacting Networks
Systems that comprise many interacting dynamical networks, such as the human
body with its biological networks or the global economic network consisting of
regional clusters, often exhibit complicated collective dynamics. To understand
the collective behavior of such systems, we investigate a model of interacting
networks exhibiting the fundamental processes of failure, damage spread, and
recovery. We find a very rich phase diagram that becomes exponentially more
complex as the number of networks is increased. In the simplest example of
interacting networks we find two critical points, 4 triple points, 10
allowed transitions, and two "forbidden" transitions, as well as complex
hysteresis loops. Remarkably, we find that triple points play the dominant role
in constructing the optimal repairing strategy in damaged interacting systems.
To support our model, we analyze an example of real interacting financial
networks and find evidence of rapid dynamical transitions between well-defined
states, in agreement with the predictions of our model.Comment: 7 figures, typos corrected, references adde
The uniqueness of company size distribution function from tent-shaped growth rate distribution
We report the proof that the extension of Gibrat's law in the middle scale
region is unique and the probability distribution function (pdf) is also
uniquely derived from the extended Gibrat's law and the law of detailed
balance. In the proof, two approximations are employed. The pdf of growth rate
is described as tent-shaped exponential functions and the value of the origin
of the growth rate distribution is constant. These approximations are confirmed
in profits data of Japanese companies 2003 and 2004. The resultant profits pdf
fits with the empirical data with high accuracy. This guarantees the validity
of the approximations.Comment: 6 pages, 5 figure
Monte Carlo-based tail exponent estimator
In this paper we propose a new approach to estimation of the tail exponent in
financial stock markets. We begin the study with the finite sample behavior of
the Hill estimator under {\alpha}-stable distributions. Using large Monte Carlo
simulations, we show that the Hill estimator overestimates the true tail
exponent and can hardly be used on samples with small length. Utilizing our
results, we introduce a Monte Carlo-based method of estimation for the tail
exponent. Our proposed method is not sensitive to the choice of tail size and
works well also on small data samples. The new estimator also gives unbiased
results with symmetrical confidence intervals. Finally, we demonstrate the
power of our estimator on the international world stock market indices. On the
two separate periods of 2002-2005 and 2006-2009, we estimate the tail exponent
Pareto's Law of Income Distribution: Evidence for Germany, the United Kingdom, and the United States
We analyze three sets of income data: the US Panel Study of Income Dynamics
PSID), the British Household Panel Survey (BHPS), and the German Socio-Economic
Panel (GSOEP). It is shown that the empirical income distribution is consistent
with a two-parameter lognormal function for the low-middle income group
(97%-99% of the population), and with a Pareto or power law function for the
high income group (1%-3% of the population). This mixture of two qualitatively
different analytical distributions seems stable over the years covered by our
data sets, although their parameters significantly change in time. It is also
found that the probability density of income growth rates almost has the form
of an exponential function.Comment: Latex2e v1.6; 16 pages with 5 figure
Growth and Fluctuations of Personal Income
Pareto's law states that the distribution of personal income obeys a
power-law in the high-income range, and has been supported by international
observations. Researchers have proposed models over a century since its
discovery. However, the dynamical nature of personal income has been little
studied hitherto, mostly due to the lack of empirical work. Here we report the
first such study, an examination of the fluctuations in personal income of
about 80,000 high-income taxpayers in Japan for two consecutive years, 1997 and
1998, when the economy was relatively stable. We find that the distribution of
the growth rate in one year is independent of income in the previous year. This
fact, combined with an approximate time-reversal symmetry, leads to the Pareto
law, thereby explaining it as a consequence of a stable economy. We also derive
a scaling relation between positive and negative growth rates, and show good
agreement with the data. These findings provide the direct observation of the
dynamical process of personal income flow not yet studied as much as for
companies.Comment: 9 pages, 4 figure
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