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Urban form has been empirically demonstrated to be of scaling invariance and can be described with fractal geometry. However, the rational range of fractal dimension value and the relationships between various fractal indicators of cities…

Physics and Society · Physics 2018-12-20 Yanguang Chen

In this paper, we study the classical problem of estimating the proportion of a finite population. First, we consider a fixed sample size method and derive an explicit sample size formula which ensures a mixed criterion of absolute and…

Statistics Theory · Mathematics 2009-02-03 Xinjia Chen

Selfsimilar space-time fractal fluctuations are generic to dynamical systems in nature such as atmospheric flows, heartbeat patterns, population dynamics, etc. The physics of the long-range correlations intrinsic to fractal fluctuations is…

General Physics · Physics 2010-12-02 A. M. Selvam

City size distributions are known to be well approximated by power laws across a wide range of countries. But such distributions are also meaningful at other spatial scales, such as within certain regions of a country. Using data from…

General Economics · Economics 2019-07-30 Tomoya Mori , Tony E. Smith , Wen-Tai Hsu

Multifractal scaling analysis of nuclear giant resonance transition probability distributions is performed within the approximation which takes into account the one-particle-one-hole (1p-1h) and 2p-2h states. A new measure to determine the…

Nuclear Theory · Physics 2016-09-08 Andrzej Z. Gorski , S. Drozdz

The spatial coverage produced by a single discrete-time random walk, with asymmetric jump probability $p\neq 1/2$ and non-uniform steps, moving on an infinite one-dimensional lattice is investigated. Analytical calculations are complemented…

Statistical Mechanics · Physics 2009-11-13 C. Anteneodo , W. A. M. Morgado

A large sample of young stellar groups is analysed aiming to investigate their clustering properties and dynamical evolution. A comparison of the Q statistical parameter, measured for the clusters, with the fractal dimension estimated for…

Solar and Stellar Astrophysics · Physics 2015-06-23 J. Gregorio-Hetem , A. Hetem , T. Santos-Silva , B. Fernandes

The methods of determining the fractal dimension and irregularity scale in simulated galaxy catalogs and the application of these methods to the data of the 2dF and 6dF catalogs are analyzed. Correlation methods are shown to be correctly…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Nikita Yu. Lovyagin

Ecosystems and other naturally resilient systems exhibit allometric scaling in the distribution of sizes of their elements. In this paper we define an allometry inspired scaling indicator for cities that is a first step towards quantifying…

Computers and Society · Computer Science 2016-04-19 Fouad Khan , Laszlo Pinter

Since the early 1970s, stellar population modelling has been one of the basic tools for understanding the physics of unresolved systems from observation of their integrated light. Models allow us to relate the integrated spectra (or…

Instrumentation and Methods for Astrophysics · Physics 2013-12-03 Miguel Cerviño

Culturomics was recently introduced as the application of high-throughput data collection and analysis to the study of human culture. Here we make use of this data by investigating fluctuations in yearly usage frequencies of specific words…

Physics and Society · Physics 2012-07-05 Jianbo Gao , Jing Hu , Xiang Mao , Matjaz Perc

Conventional statistics begins with a model, and assigns a likelihood of obtaining any particular set of data. The opposite approach, beginning with the data and assigning a likelihood to any particular model, is explored here for the case…

Data Analysis, Statistics and Probability · Physics 2009-10-30 Timothy E. Holy

The distribution of living languages is investigated and scaling relations are found for the diversity of languages as a function of the country area and population. These results are compared with data from Ecology and from computer…

Physics and Society · Physics 2009-11-11 M. A. F. Gomes , G. L. Vasconcelos , I. J. Tsang , I. R. Tsang

This article is a presentation of specific recent results describing scaling limits of individual-based models. Thanks to them, we wish to relate the time-scales typical of demographic dynamics and natural selection to the parameters of the…

Probability · Mathematics 2023-08-01 Aurélien Velleret

Records of the traded value f_i(t) of stocks display fluctuation scaling, a proportionality between the standard deviation sigma(i) and the average <f(i)>: sigma(i) ~ f(i)^alpha, with a strong time scale dependence alpha(dt). The…

Physics and Society · Physics 2008-12-02 Zoltan Eisler , Janos Kertesz

In this study, we present a method to measure changes over time of fractal dimension. We confirmed that our method can calculate the fractal dimension with the same precision as conventional methods, and tracking performance of our method…

Numerical Analysis · Computer Science 2013-10-15 Satoshi Hasegawa , Hajime Anada , Shuya Kanagawa

The ISI-Impact Factors suffer from a number of drawbacks, among them the statistics-why should one use the mean and not the median?-and the incomparability among fields of science because of systematic differences in citation behavior among…

Digital Libraries · Computer Science 2010-09-23 Loet Leydesdorff , Lutz Bornmann

Fractional scoring has been proposed to avoid inconsistencies in the attribution of publications to percentile rank classes. Uncertainties and ambiguities in the evaluation of percentile ranks can be demonstrated most easily with small…

Digital Libraries · Computer Science 2013-03-25 Michael Schreiber

We consider a nonlocal Fisher-KPP equation that models a population structured in space and in phenotype. The population lives in a heterogeneous periodic environment: the diffusion coefficient, the mutation coefficient and the fitness of…

Analysis of PDEs · Mathematics 2024-10-28 Nathanaël Boutillon

We introduce a model for the dynamics of mud cracking in the limit of of extremely thin layers. In this model the growth of fracture proceeds by selecting the part of the material with the smallest (quenched) breaking threshold. In…

Condensed Matter · Physics 2009-10-31 A. Gabrielli , R. Cafiero , G. Caldarelli