Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers
The fish discards surveys, conducted by Northern Ireland, Spain and England under the auspices of EC project 95/094, are multistage in design with a structure of hauls within trips within vessels. The data collected by on-board observers from these surveys enabled investigation into the optimal numb...
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Online Access: | http://hdl.handle.net/10508/8896 http://hdl.handle.net/10261/328743 https://doi.org/10.1016/S0165-7836(01)00308-3 |
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ftcsic:oai:digital.csic.es:10261/328743 2024-02-11T10:06:31+01:00 Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers Allen, Michelle Kilpatrick, David Armstrong, Mike Briggs, Richard Course, Grant Pérez-Contreras, María Nélida Atlantic Ocean North Atlantic Northeast Atlantic Irish Sea Bay of Biscay 2002 http://hdl.handle.net/10508/8896 http://hdl.handle.net/10261/328743 https://doi.org/10.1016/S0165-7836(01)00308-3 en eng Centro Oceanográfico de Vigo VoR http://www.sciencedirect.com/science/article/pii/S0165783601003083 Fisheries Research, 55(1-3). 2002: 11-24 0165-7836 http://hdl.handle.net/10508/8896 http://hdl.handle.net/10261/328743 doi:10.1016/S0165-7836(01)00308-3 20669 open Fishery surveys Centro Oceanográfico de Vigo Pesquerías Fish discards Multistage sampling Optimum sample size Variance components Celtic Sea Irish Sea North Sea Bay of Biscay research article 2002 ftcsic https://doi.org/10.1016/S0165-7836(01)00308-3 2024-01-16T11:49:29Z The fish discards surveys, conducted by Northern Ireland, Spain and England under the auspices of EC project 95/094, are multistage in design with a structure of hauls within trips within vessels. The data collected by on-board observers from these surveys enabled investigation into the optimal number of hauls, trips and vessels that require sampling to achieve target levels of precision for each gear type and country. Residual maximum likelihood (REML) was used to estimate the variance components between vessels, between trips within vessels and between hauls within trips within vessels, while examining the significance of the fixed effects of area, quarter and their interaction. To meet the REML requirement that the data are normally distributed, the extreme skewness of the data was corrected by a natural log transformation. The estimated lognormal variance components were used within the multistage formulae to estimate the optimal average sampling levels at each stage. The results showed that more resources than were available during the project were required to achieve a coefficient of variation of 20% for the estimation of discard levels for Northern Ireland twin-rig and Spanish pair trawls. SI Article in Journal/Newspaper North Atlantic Northeast Atlantic Digital.CSIC (Spanish National Research Council) Fisheries Research 55 1-3 11 24 |
institution |
Open Polar |
collection |
Digital.CSIC (Spanish National Research Council) |
op_collection_id |
ftcsic |
language |
English |
topic |
Fishery surveys Centro Oceanográfico de Vigo Pesquerías Fish discards Multistage sampling Optimum sample size Variance components Celtic Sea Irish Sea North Sea Bay of Biscay |
spellingShingle |
Fishery surveys Centro Oceanográfico de Vigo Pesquerías Fish discards Multistage sampling Optimum sample size Variance components Celtic Sea Irish Sea North Sea Bay of Biscay Allen, Michelle Kilpatrick, David Armstrong, Mike Briggs, Richard Course, Grant Pérez-Contreras, María Nélida Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers |
topic_facet |
Fishery surveys Centro Oceanográfico de Vigo Pesquerías Fish discards Multistage sampling Optimum sample size Variance components Celtic Sea Irish Sea North Sea Bay of Biscay |
description |
The fish discards surveys, conducted by Northern Ireland, Spain and England under the auspices of EC project 95/094, are multistage in design with a structure of hauls within trips within vessels. The data collected by on-board observers from these surveys enabled investigation into the optimal number of hauls, trips and vessels that require sampling to achieve target levels of precision for each gear type and country. Residual maximum likelihood (REML) was used to estimate the variance components between vessels, between trips within vessels and between hauls within trips within vessels, while examining the significance of the fixed effects of area, quarter and their interaction. To meet the REML requirement that the data are normally distributed, the extreme skewness of the data was corrected by a natural log transformation. The estimated lognormal variance components were used within the multistage formulae to estimate the optimal average sampling levels at each stage. The results showed that more resources than were available during the project were required to achieve a coefficient of variation of 20% for the estimation of discard levels for Northern Ireland twin-rig and Spanish pair trawls. SI |
format |
Article in Journal/Newspaper |
author |
Allen, Michelle Kilpatrick, David Armstrong, Mike Briggs, Richard Course, Grant Pérez-Contreras, María Nélida |
author_facet |
Allen, Michelle Kilpatrick, David Armstrong, Mike Briggs, Richard Course, Grant Pérez-Contreras, María Nélida |
author_sort |
Allen, Michelle |
title |
Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers |
title_short |
Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers |
title_full |
Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers |
title_fullStr |
Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers |
title_full_unstemmed |
Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers |
title_sort |
multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers |
publishDate |
2002 |
url |
http://hdl.handle.net/10508/8896 http://hdl.handle.net/10261/328743 https://doi.org/10.1016/S0165-7836(01)00308-3 |
op_coverage |
Atlantic Ocean North Atlantic Northeast Atlantic Irish Sea Bay of Biscay |
genre |
North Atlantic Northeast Atlantic |
genre_facet |
North Atlantic Northeast Atlantic |
op_relation |
Centro Oceanográfico de Vigo VoR http://www.sciencedirect.com/science/article/pii/S0165783601003083 Fisheries Research, 55(1-3). 2002: 11-24 0165-7836 http://hdl.handle.net/10508/8896 http://hdl.handle.net/10261/328743 doi:10.1016/S0165-7836(01)00308-3 20669 |
op_rights |
open |
op_doi |
https://doi.org/10.1016/S0165-7836(01)00308-3 |
container_title |
Fisheries Research |
container_volume |
55 |
container_issue |
1-3 |
container_start_page |
11 |
op_container_end_page |
24 |
_version_ |
1790604299191975936 |