The consecutive disparity index, D : a measure of temporal variability in ecological studies
Fernández-Martínez, Marcos (Universiteit Antwerpen. Departement Biologie)
Vicca, Sara (Universiteit Antwerpen. Departement Biologie)
Janssens, Ivan (Universiteit Antwerpen. Departement Biologie)
Carnicer i Cols, Jofre (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Martín Vide, Javier (Universitat de Barcelona. Grup de Climatologia)
Peñuelas, Josep (Centre de Recerca Ecològica i d'Aplicacions Forestals)

Data:	2018
Resum:	Temporal variability in ecological processes has attracted the attention of many disciplines in ecology, which has resulted in the development of several quantitative indices. The coefficient of variation (CV = standard deviation × mean−1) is still one of the most commonly used indices to assess temporal variability, despite being known to present several problems on its assessment (e. g. , mean dependence or high sensitivity to rare events). The proportional variability (PV) index was developed to solve some of the CV's drawbacks, but, so far, no variability index takes into account the chronological order of the values in time series. In this paper, we introduce the consecutive disparity index (D), a temporal variability index that takes into account the chronological order of the values, assessing the average rate of change between consecutive values. We used computer simulations and empirical data for fruit production in trees, bird counts, and rodent captures to compare the behavior of D, PV, and CV under different scenarios. D was sensitive to changes in temporal autocorrelation in the negative autocorrelation range, and CV and PV were sensitive in the positive autocorrelation range despite not considering the chronological order of the values. The CV, however, was highly dependent on the mean of the time series, while D and PV were not. Our results demonstrate that, like PV, D solves many of the problems of the CV index while taking into account the chronological order of values in time series. The mathematical and statistical features of D make it a suitable index for analyzing temporal variability in a wide range of ecological studies.
Ajuts:	European Commission 610028 Ministerio de Economía y Competitividad CGL2016-79835-P Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-274 Agència de Gestió d'Ajuts Universitaris i de Recerca FI-2013
Drets:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Llengua:	Anglès
Document:	Article ; recerca ; Versió publicada
Matèria:	Coefficient of variation ; Disparity ; Proportional variability ; Temporal dynamics
Publicat a:	Ecosphere, Vol. 9, issue 12 (Dec. 2018) , e025272018, ISSN 2150-8925

DOI: 10.1002/ecs2.2527

Article 13 p, 3.3 MB

Material suplementari 1 p, 185.0 KB

El registre apareix a les col·leccions:
Documents de recerca > Documents dels grups de recerca de la UAB > Centres i grups de recerca (producció científica) > Ciències > CREAF (Centre de Recerca Ecològica i d'Aplicacions Forestals) > Imbalance-P
Articles > Articles de recerca
Articles > Articles publicats