Journal of Mathematical Biology

, Volume 57, Issue 4, pp 537–555

Robust hypothesis tests for independence in community assembly


DOI: 10.1007/s00285-008-0176-0

Cite this article as:
Ladau, J. & Schwager, S.J. J. Math. Biol. (2008) 57: 537. doi:10.1007/s00285-008-0176-0


The extent to which competition affects the distributions of species at large spatial scales is unclear. To evaluate this question, hypothesis tests that do not depend on parametric assumptions are needed. Here, we develop a broadly applicable test that requires only one parametric assumption. Letting i and j denote the ith and jth colonists to arrive at a site, respectively, and \({\langle ij \rangle}\) the event that i and j belong to the same “unit” (e.g., functional group, genus), we show how colonists will be partitioned into units if for all i and j, \({\langle ij \rangle}\) is independent of whether i and j share unit membership with the other colonists, conditional on other information about shared units. Our distribution of partitions is useful for inferring competitive effects, because these effects predict that for at least one i and j, \({P(\langle ij \rangle)}\) will be less when i and j share unit membership than when they do not.


Competition Community ecology Functional group Null model test Set partition Integer partition 

Mathematics Subject Classification (2000)

60E05 62G10 92B10 92B15 62E15 

Supplementary material

285_2008_176_MOESM1_ESM.pdf (270 kb)
ESM 1 (PDF 270 kb)

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Santa Fe InstituteSanta FeUSA
  2. 2.Department of Biological Statistics and Computational BiologyCornell UniversityIthacaUSA