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Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity
The pooling robustness property of distance sampling results in unbiased abundance estimation even when sources of variation in detection probability are not modeled. However, this property cannot be relied upon to produce unbiased subpopulation abundance estimates when using a single pooled detecti...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
John Wiley and Sons Inc.
2023
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9817188/ https://www.ncbi.nlm.nih.gov/pubmed/36620408 http://dx.doi.org/10.1002/ece3.9684 |
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author | Rexstad, Eric Buckland, Steve Marshall, Laura Borchers, David |
author_facet | Rexstad, Eric Buckland, Steve Marshall, Laura Borchers, David |
author_sort | Rexstad, Eric |
collection | PubMed |
description | The pooling robustness property of distance sampling results in unbiased abundance estimation even when sources of variation in detection probability are not modeled. However, this property cannot be relied upon to produce unbiased subpopulation abundance estimates when using a single pooled detection function that ignores subpopulations. We investigate by simulation the effect of differences in subpopulation detectability upon bias in subpopulation abundance estimates. We contrast subpopulation abundance estimates using a pooled detection function with estimates derived using a detection function model employing a subpopulation covariate. Using point transect survey data from a multispecies songbird study, species‐specific abundance estimates are compared using pooled detection functions with and without a small number of adjustment terms, and a detection function with species as a covariate. With simulation, we demonstrate the bias of subpopulation abundance estimates when a pooled detection function is employed. The magnitude of the bias is positively related to the magnitude of disparity between the subpopulation detection functions. However, the abundance estimate for the entire population remains unbiased except when there is extreme heterogeneity in detection functions. Inclusion of a detection function model with a subpopulation covariate essentially removes the bias of the subpopulation abundance estimates. The analysis of the songbird point count surveys shows some bias in species‐specific abundance estimates when a pooled detection function is used. Pooling robustness is a unique property of distance sampling, producing unbiased abundance estimates at the level of the study area even in the presence of large differences in detectability between subpopulations. In situations where subpopulation abundance estimates are required for data‐poor subpopulations and where the subpopulations can be identified, we recommend the use of subpopulation as a covariate to reduce bias induced in subpopulation abundance estimates. |
format | Online Article Text |
id | pubmed-9817188 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2023 |
publisher | John Wiley and Sons Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-98171882023-01-06 Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity Rexstad, Eric Buckland, Steve Marshall, Laura Borchers, David Ecol Evol Research Articles The pooling robustness property of distance sampling results in unbiased abundance estimation even when sources of variation in detection probability are not modeled. However, this property cannot be relied upon to produce unbiased subpopulation abundance estimates when using a single pooled detection function that ignores subpopulations. We investigate by simulation the effect of differences in subpopulation detectability upon bias in subpopulation abundance estimates. We contrast subpopulation abundance estimates using a pooled detection function with estimates derived using a detection function model employing a subpopulation covariate. Using point transect survey data from a multispecies songbird study, species‐specific abundance estimates are compared using pooled detection functions with and without a small number of adjustment terms, and a detection function with species as a covariate. With simulation, we demonstrate the bias of subpopulation abundance estimates when a pooled detection function is employed. The magnitude of the bias is positively related to the magnitude of disparity between the subpopulation detection functions. However, the abundance estimate for the entire population remains unbiased except when there is extreme heterogeneity in detection functions. Inclusion of a detection function model with a subpopulation covariate essentially removes the bias of the subpopulation abundance estimates. The analysis of the songbird point count surveys shows some bias in species‐specific abundance estimates when a pooled detection function is used. Pooling robustness is a unique property of distance sampling, producing unbiased abundance estimates at the level of the study area even in the presence of large differences in detectability between subpopulations. In situations where subpopulation abundance estimates are required for data‐poor subpopulations and where the subpopulations can be identified, we recommend the use of subpopulation as a covariate to reduce bias induced in subpopulation abundance estimates. John Wiley and Sons Inc. 2023-01-06 /pmc/articles/PMC9817188/ /pubmed/36620408 http://dx.doi.org/10.1002/ece3.9684 Text en © 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. https://creativecommons.org/licenses/by/4.0/This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Research Articles Rexstad, Eric Buckland, Steve Marshall, Laura Borchers, David Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity |
title | Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity |
title_full | Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity |
title_fullStr | Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity |
title_full_unstemmed | Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity |
title_short | Pooling robustness in distance sampling: Avoiding bias when there is unmodelled heterogeneity |
title_sort | pooling robustness in distance sampling: avoiding bias when there is unmodelled heterogeneity |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9817188/ https://www.ncbi.nlm.nih.gov/pubmed/36620408 http://dx.doi.org/10.1002/ece3.9684 |
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