O-Stats, or Pairwise Community-Level Niche Overlap Statistics
c(person(c('Quentin', 'D.'), 'Read', role = c('aut', 'cre'), email = 'qread@sesync.org'),
person('Arya', 'Yue', role = 'aut'),
person(c('Isadora', 'E.'), 'Fluck', role = 'aut'),
person('Benjamin', 'Baiser', role = 'aut'),
person(c('John', 'M.'), 'Grady', role = 'aut'),
person(c('Phoebe', 'L.'), 'Zarnetske', role = 'aut'),
person('Sydne', 'Record', role = 'aut')
)
O-statistics, or overlap statistics, measure the degree of community-level trait overlap.
They are estimated by fitting nonparametric kernel density functions to each species’ trait
distribution and calculating their areas of overlap. For instance, the median pairwise overlap
for a community is calculated by first determining the overlap of each species pair
in trait space, and then taking the median overlap of each species pair in a community.
This median overlap value is called the O-statistic (O for overlap).
The Ostats() function calculates separate univariate overlap statistics for each trait,
while the Ostats_multivariate() function calculates a single multivariate overlap statistic for all traits.
O-statistics can be evaluated against null models to obtain standardized effect sizes.
Ostats is part of the collaborative Macrosystems Biodiversity Project "Local- to continental-scale
drivers of biodiversity across the National Ecological Observatory Network (NEON)."
For more information on this project, see the Macrosystems Biodiversity Website
(<https://neon-biodiversity.github.io/>). Calculation of O-statistics is described in
Read et al. (2018) <doi:10.1111/ecog.03641>, and a teaching module for introducing the
underlying biological concepts at an undergraduate level is described in Grady et al.
(2018) <http://tiee.esa.org/vol/v14/issues/figure_sets/grady/abstract.html>.
sfsmisc, matrixStats, circular, hypervolume, ggplot2,
gridExtra, viridis, grid, MASS
Quentin D. Read [aut, cre],
Arya Yue [aut],
Isadora E. Fluck [aut],
Benjamin Baiser [aut],
John M. Grady [aut],
Phoebe L. Zarnetske [aut],
Sydne Record [aut]