skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Novel covariance-based neutrality test of time-series data reveals asymmetries in ecological and economic systems

Journal Article · · PLoS Computational Biology (Online)
ORCiD logo [1];  [2];  [2];  [3]
  1. Duke Univ., Durham, NC (United States)
  2. Princeton Univ., Princeton, NJ (United States)
  3. Univ. of Chicago, Chicago, IL (United States)

Systems as diverse as the interacting species in a community, alleles at a genetic locus, and companies in a market are characterized by competition (over resources, space, capital, etc) and adaptation. Neutral theory, built around the hypothesis that individual performance is independent of group membership, has found utility across the disciplines of ecology, population genetics, and economics, both because of the success of the neutral hypothesis in predicting system properties and because deviations from these predictions provide information about the underlying dynamics. However, most tests of neutrality are weak, based on static system properties such as species-abundance distributions or the number of singletons in a sample. Time-series data provide a window onto a system’s dynamics, and should furnish tests of the neutral hypothesis that are more powerful to detect deviations from neutrality and more informative about to the type of competitive asymmetry that drives the deviation. Here, we present a neutrality test for time-series data. We apply this test to several microbial time-series and financial time-series and find that most of these systems are not neutral. Our test isolates the covariance structure of neutral competition, thus facilitating further exploration of the nature of asymmetry in the covariance structure of competitive systems. Much like neutrality tests from population genetics that use relative abundance distributions have enabled researchers to scan entire genomes for genes under selection, we anticipate our time-series test will be useful for quick significance tests of neutrality across a range of ecological, economic, and sociological systems for which time-series data are available. Here, future work can use our test to categorize and compare the dynamic fingerprints of particular competitive asymmetries (frequency dependence, volatility smiles, etc) to improve forecasting and management of complex adaptive systems.

Research Organization:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
AC02-09CH11466
OSTI ID:
1335699
Journal Information:
PLoS Computational Biology (Online), Vol. 12, Issue 9; ISSN 1553-7358
Publisher:
Public Library of ScienceCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 8 works
Citation information provided by
Web of Science

References (34)

A Heteroskedasticity-Consistent Covariance Matrix Estimator and a Direct Test for Heteroskedasticity journal May 1980
Neutral theory in community ecology and the hypothesis of functional equivalence journal February 2005
Neutral theory as a predictor of avifaunal extinctions after habitat loss journal January 2011
The Pricing of Options and Corporate Liabilities journal May 1973
Stochastic models and simulation of ion channel dynamics journal May 2010
Stochastic Population Dynamics in Ecology and Conservation book April 2003
Relative arbitrage in volatility-stabilized markets journal April 2005
Prey Carrying Capacity Modulates the Effect of Predation on Prey Diversity journal September 2015
Comparing models of species abundance (Reply) journal May 2006
Comparing models of species abundance journal May 2006
Niche versus Neutrality: A Dynamical Analysis journal October 2014
Applications of Stochastic Portfolio Theory book January 2002
Human Microbiome in Health and Disease journal February 2012
The Units of Selection journal November 1970
Probability Models for DNA Sequence Evolution book January 2008
Random drift and culture change
  • Bentley, R. Alexander; Hahn, Matthew W.; Shennan, Stephen J.
  • Proceedings of the Royal Society of London. Series B: Biological Sciences, Vol. 271, Issue 1547 https://doi.org/10.1098/rspb.2004.2746
journal July 2004
Hitchhiking Under Positive Darwinian Selection journal July 2000
Neutral theory and relative species abundance in ecology journal August 2003
Temporal variability of forest communities: empirical estimates of population change in 4000 tree species journal May 2014
Analysis of market weights under volatility-stabilized market models journal June 2011
Moving pictures of the human microbiome journal January 2011
Complexity and the Economy journal April 1999
Empirical Evaluation of Neutral Theory journal June 2006
Ecosystems and the Biosphere as Complex Adaptive Systems journal September 1998
Evolution of Character Displacement in Darwin's Finches journal July 2006
Neutral theory: a historical perspective journal November 2007
Best Practices for Binary and Ordinal Data Analyses journal January 2021
Pharmacokinetics of Probiotics and Biotherapeutic Agents in Humans journal January 1998
The genetical theory of natural selection. book January 1930
Goodness-of-fit tests with dependent observations journal September 2011
Evolution in Mendelian Populations journal March 1931
Interspecific competition increases local extinction rate in a metapopulation system journal August 1989
Diet rapidly and reproducibly alters the human gut microbiome journal December 2013
Statistical method for testing the neutral mutation hypothesis by DNA polymorphism. journal November 1989

Cited By (5)

Phylofactorization - theory and challenges posted_content September 2017
Phylofactorization: a graph-partitioning algorithm to identify phylogenetic scales of ecological data posted_content January 2018
Phylofactorization: a graph partitioning algorithm to identify phylogenetic scales of ecological data journal February 2019
Use and abuse of correlation analyses in microbial ecology journal June 2019
Signatures of ecological processes in microbial community time series journal June 2018