A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data
Trawl survey data with high spatial and seasonal coverage were analysed using a variant of the Log Gaussian Cox Process (LGCP) statistical model to estimate unbiased relative fish densities. The model estimates correlations between observations according to time, space, and fish size and includes ze...
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ftrepec:oai:RePEc:plo:pone00:0099151 2024-04-14T08:11:51+00:00 A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data J Rasmus Nielsen Kasper Kristensen Peter Lewy Francois Bastardie https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099151 https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0099151&type=printable unknown https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099151 https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0099151&type=printable article ftrepec 2024-03-19T10:28:45Z Trawl survey data with high spatial and seasonal coverage were analysed using a variant of the Log Gaussian Cox Process (LGCP) statistical model to estimate unbiased relative fish densities. The model estimates correlations between observations according to time, space, and fish size and includes zero observations and over-dispersion. The model utilises the fact the correlation between numbers of fish caught increases when the distance in space and time between the fish decreases, and the correlation between size groups in a haul increases when the difference in size decreases. Here the model is extended in two ways. Instead of assuming a natural scale size correlation, the model is further developed to allow for a transformed length scale. Furthermore, in the present application, the spatial- and size-dependent correlation between species was included. For cod (Gadus morhua) and whiting (Merlangius merlangus), a common structured size correlation was fitted, and a separable structure between the time and space-size correlation was found for each species, whereas more complex structures were required to describe the correlation between species (and space-size). The within-species time correlation is strong, whereas the correlations between the species are weaker over time but strong within the year. Article in Journal/Newspaper Gadus morhua RePEc (Research Papers in Economics) |
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RePEc (Research Papers in Economics) |
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Trawl survey data with high spatial and seasonal coverage were analysed using a variant of the Log Gaussian Cox Process (LGCP) statistical model to estimate unbiased relative fish densities. The model estimates correlations between observations according to time, space, and fish size and includes zero observations and over-dispersion. The model utilises the fact the correlation between numbers of fish caught increases when the distance in space and time between the fish decreases, and the correlation between size groups in a haul increases when the difference in size decreases. Here the model is extended in two ways. Instead of assuming a natural scale size correlation, the model is further developed to allow for a transformed length scale. Furthermore, in the present application, the spatial- and size-dependent correlation between species was included. For cod (Gadus morhua) and whiting (Merlangius merlangus), a common structured size correlation was fitted, and a separable structure between the time and space-size correlation was found for each species, whereas more complex structures were required to describe the correlation between species (and space-size). The within-species time correlation is strong, whereas the correlations between the species are weaker over time but strong within the year. |
format |
Article in Journal/Newspaper |
author |
J Rasmus Nielsen Kasper Kristensen Peter Lewy Francois Bastardie |
spellingShingle |
J Rasmus Nielsen Kasper Kristensen Peter Lewy Francois Bastardie A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data |
author_facet |
J Rasmus Nielsen Kasper Kristensen Peter Lewy Francois Bastardie |
author_sort |
J Rasmus Nielsen |
title |
A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data |
title_short |
A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data |
title_full |
A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data |
title_fullStr |
A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data |
title_full_unstemmed |
A Statistical Model for Estimation of Fish Density Including Correlation in Size, Space, Time and between Species from Research Survey Data |
title_sort |
statistical model for estimation of fish density including correlation in size, space, time and between species from research survey data |
url |
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099151 https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0099151&type=printable |
genre |
Gadus morhua |
genre_facet |
Gadus morhua |
op_relation |
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099151 https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0099151&type=printable |
_version_ |
1796309586783764480 |