Incorporating survey variance in sequential population analysis ...
No abstracts are to be cited without prior reference to the author.We derive some basic statistics that describe the variability of a survey index derived from stratified random sampling for several Northwest Atlantic fish stocks. The variability is expressed as a function of population abundance an...
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ftdatacite:10.17895/ices.pub.25074293.v1 2024-03-31T07:54:36+00:00 Incorporating survey variance in sequential population analysis ... Cadigan, Noel 2024 https://dx.doi.org/10.17895/ices.pub.25074293.v1 https://ices-library.figshare.com/articles/conference_contribution/Incorporating_survey_variance_in_sequential_population_analysis/25074293/1 unknown ASC 2009 - Theme session N https://ices-library.figshare.com/ICES-ASC-2009/groups https://dx.doi.org/10.17895/ices.pub.25074293 https://ices-library.figshare.com/ICES-ASC-2009/groups ICES Custom Licence https://www.ices.dk/Pages/library_policies.aspx Fisheries and aquaculture Technologies and data Conference contribution article CreativeWork Other 2024 ftdatacite https://doi.org/10.17895/ices.pub.25074293.v110.17895/ices.pub.25074293 2024-03-04T12:15:15Z No abstracts are to be cited without prior reference to the author.We derive some basic statistics that describe the variability of a survey index derived from stratified random sampling for several Northwest Atlantic fish stocks. The variability is expressed as a function of population abundance and is based on a Negative Binomial (NB) distribution assumption for trawl catches. Diagnostics that support this assumption are presented. However, maximum likelihood estimates of the NB over-dispersion parameter based on a stratumeffects model can have severe bias, and an alternative estimator is shown to give much better results. We also show how the survey variance component can be incorporated into stock assessment models like ADAPT or XSA. Interestingly, this results in an estimation procedure that is more similar to the implicit and intuitive weighting that many fisheries scientists use to track cohorts in survey data by focusing on the ages that tend to be caught well, whereas ADAPT or XSA tend to give ... Conference Object Northwest Atlantic DataCite Metadata Store (German National Library of Science and Technology) |
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DataCite Metadata Store (German National Library of Science and Technology) |
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topic |
Fisheries and aquaculture Technologies and data |
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Fisheries and aquaculture Technologies and data Cadigan, Noel Incorporating survey variance in sequential population analysis ... |
topic_facet |
Fisheries and aquaculture Technologies and data |
description |
No abstracts are to be cited without prior reference to the author.We derive some basic statistics that describe the variability of a survey index derived from stratified random sampling for several Northwest Atlantic fish stocks. The variability is expressed as a function of population abundance and is based on a Negative Binomial (NB) distribution assumption for trawl catches. Diagnostics that support this assumption are presented. However, maximum likelihood estimates of the NB over-dispersion parameter based on a stratumeffects model can have severe bias, and an alternative estimator is shown to give much better results. We also show how the survey variance component can be incorporated into stock assessment models like ADAPT or XSA. Interestingly, this results in an estimation procedure that is more similar to the implicit and intuitive weighting that many fisheries scientists use to track cohorts in survey data by focusing on the ages that tend to be caught well, whereas ADAPT or XSA tend to give ... |
format |
Conference Object |
author |
Cadigan, Noel |
author_facet |
Cadigan, Noel |
author_sort |
Cadigan, Noel |
title |
Incorporating survey variance in sequential population analysis ... |
title_short |
Incorporating survey variance in sequential population analysis ... |
title_full |
Incorporating survey variance in sequential population analysis ... |
title_fullStr |
Incorporating survey variance in sequential population analysis ... |
title_full_unstemmed |
Incorporating survey variance in sequential population analysis ... |
title_sort |
incorporating survey variance in sequential population analysis ... |
publisher |
ASC 2009 - Theme session N |
publishDate |
2024 |
url |
https://dx.doi.org/10.17895/ices.pub.25074293.v1 https://ices-library.figshare.com/articles/conference_contribution/Incorporating_survey_variance_in_sequential_population_analysis/25074293/1 |
genre |
Northwest Atlantic |
genre_facet |
Northwest Atlantic |
op_relation |
https://ices-library.figshare.com/ICES-ASC-2009/groups https://dx.doi.org/10.17895/ices.pub.25074293 https://ices-library.figshare.com/ICES-ASC-2009/groups |
op_rights |
ICES Custom Licence https://www.ices.dk/Pages/library_policies.aspx |
op_doi |
https://doi.org/10.17895/ices.pub.25074293.v110.17895/ices.pub.25074293 |
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1795035594368221184 |