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We apply the scale-length method to several three dimensional samples of the Two degree Field Galaxy Redshift Survey. This method allows us to map in a quantitative and powerful way large scale structures in the distribution of galaxies…

Astrophysics · Physics 2009-08-03 Francesco Sylos Labini , Nikolay L. Vasilyev , Yurij V. Baryshev

The effects of spatial correlations of density fluctuations on merger histories of dark matter haloes (so-called `{\it merger trees}') are analysed. We compare the mass functions of dark haloes derived by a new method for calculating merger…

Astrophysics · Physics 2015-06-24 Masahiro Nagashima , Naoteru Gouda

We present new theoretical and empirical results on the probability distributions of species persistence times in natural ecosystems. Persistence times, defined as the timespans occurring between species' colonization and local extinction…

Populations and Evolution · Quantitative Biology 2012-03-21 S. Suweis , E. Bertuzzo , L. Mari , I. Rodriguez-Iturbe , A. Maritan , A. Rinaldo

A new model ecosystem consisting of many interacting species is introduced. The species are connected through a random matrix with a given connectivity. It is shown that the system is organized close to a boundary of marginal stability in…

adap-org · Physics 2007-05-23 Ricard V. Sole , David Alonso , Alan McKane

Ecological patterns arise from the interplay of many different processes, and yet the emergence of consistent phenomena across a diverse range of ecological systems suggests that many patterns may in part be determined by statistical or…

Populations and Evolution · Quantitative Biology 2015-11-16 Xiao Xiao , James P. O'Dwyer , Ethan P. White

Fire is an indissoluble component of ecosystems, however quantifying the effects of fire on vegetation is challenging task as fire lies outside the typical experimental design attributes. A recent simulation study showed that under…

Populations and Evolution · Quantitative Biology 2014-12-16 Aristides Moustakas

Taylor's law, also known as fluctuation scaling in physics and the power-law variance function in statistics, is an empirical pattern widely observed across fields including ecology, physics, finance, and epidemiology. It states that the…

Statistics Theory · Mathematics 2025-10-13 Pok Him Cheng , Joel E. Cohen , Hok Kan Ling , Sheung Chi Phillip Yam

In the last years there has been a growing interest in the understanding a vast variety of scale invariant and critical phenomena occurring in nature. Experiments and observations indeed suggest that many physical systems develop…

Astrophysics · Physics 2019-08-17 L. Pietronero , F. Sylos Labini , M. Montuori

The spatial arrangement of trees in a tropical forest reflects the interplay between aggregating processes, like dispersal limitation, and negative feedback that induces effective repulsion among individuals. Monitoring the variance-mean…

Populations and Evolution · Quantitative Biology 2014-11-11 Efrat Seri , Nadav M. Shnerb

The most common statistic used to analyze large-scale structure surveys is the correlation function, or power spectrum. Here, we show how `slicing' the correlation function on local density brings sensitivity to interesting non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-15 Mark C. Neyrinck , István Szapudi , Nuala McCullagh , Alex Szalay , Bridget Falck , Jie Wang

During the last decades macroecology has identified broad-scale patterns of abundances and diversity of microbial communities and put forward some potential explanations for them. However, these advances are not paralleled by a full…

Populations and Evolution · Quantitative Biology 2024-01-26 José Camacho-Mateu , Aniello Lampo , Matteo Sireci , Miguel Ángel Muñoz , José A. Cuesta

The occurrence and the distribution of patterns of trees associated to natural numbers are investigated. Bounds from above and below are proven for certain natural quantities.

Number Theory · Mathematics 2024-01-09 Roberto Conti , Pierluigi Contucci , Vitalii Iudelevich

We present an analytically tractable variant of the voter model that provides a quantitatively accurate description of beta-diversity (two-point correlation function) in two tropical forests. The model exhibits novel scaling behavior that…

Populations and Evolution · Quantitative Biology 2007-05-23 Tommaso Zillio , Igor Volkov , Jayanth R. Banavar , Stephen P. Hubbell , Amos Maritan

We investigate the relevance of {\sl self-organized criticality (SOC)} models in previously published empirical datasets, which includes statistical observations in astrophysics, geophysics, biophysics, sociophysics, and informatics. We…

Instrumentation and Methods for Astrophysics · Physics 2025-05-05 Markus J. Aschwanden , Felix Scholkmann

The growth of complex populations, such as microbial communities, forests, and cities, occurs over vastly different spatial and temporal scales. Although research in different fields has developed detailed, system-specific models to…

Populations and Evolution · Quantitative Biology 2023-09-14 Ashish B. George , James O'Dwyer

We present Collaborative Trees, a novel tree model designed for regression prediction, along with its bagging version, which aims to analyze complex statistical associations between features and uncover potential patterns inherent in the…

Methodology · Statistics 2024-05-21 Chien-Ming Chi

We propose a general model to study the interplay between spatial dispersal and environment spatiotemporal fluctuations in metapopulation dynamics. An ecological landscape of favorable patches is generated like a L\'{e}vy dust, which allows…

Populations and Evolution · Quantitative Biology 2015-08-20 E. H. Colombo , C. Anteneodo

A model of interacting random walkers is presented and shown to give rise to patterns consisting in periodic arrangements of fluctuating particle clusters. The model represents biological individuals that die or reproduce at rates depending…

Statistical Mechanics · Physics 2009-11-10 Cristobal Lopez , Emilio Hernandez-Garcia

Taylor's power law (or fluctuation scaling) states that on comparable populations, the variance of each sample is approximately proportional to a power of the mean of the population. It has been shown to hold by empirical observations in a…

Statistics Theory · Mathematics 2020-10-22 Victor De la Pena , Paul Doukhan , Yahia Salhi

One of the first beings affected by changes in the climate are trees, one of our most vital resources. In this study tree species interaction and the response to climate in different ecological environments is observed by applying a joint…

Populations and Evolution · Quantitative Biology 2019-10-14 Hyun Choi , Ali Sadeghian , Sergio Marconi , Ethan White , Daisy Zhe Wang