Double-Observer Line Transect Methods: Levels of Independence
Double-observer line transect methods are becoming increasingly widespread, especially for the estimation of marine mammal abundance from aerial and shipboard surveys when detection of animals on the line is uncertain. The resulting data supplement conventional distance sampling data with two-sample...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.385.5432 2023-05-15T17:12:51+02:00 Double-Observer Line Transect Methods: Levels of Independence Stephen T. Buckl Jeffrey L. Laake David L. Borchers The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.385.5432 http://www.creem.st-and.ac.uk/stb/ms 080447MR levels of independence.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.385.5432 http://www.creem.st-and.ac.uk/stb/ms 080447MR levels of independence.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www.creem.st-and.ac.uk/stb/ms 080447MR levels of independence.pdf KEY WORDS Distance sampling Double-observer methods Full independence Limiting independence Line transect sampling Point independence text ftciteseerx 2016-09-18T00:32:02Z Double-observer line transect methods are becoming increasingly widespread, especially for the estimation of marine mammal abundance from aerial and shipboard surveys when detection of animals on the line is uncertain. The resulting data supplement conventional distance sampling data with two-sample mark-recapture data. Like conventional mark-recapture data, these have inherent problems for estimating abundance in the presence of heterogeneity. Unlike conventional mark-recapture methods, line transect methods use knowledge of the distribution of a covariate which affects detection probability (namely distance from the transect line) in inference. This knowledge can be used to diagnose unmodelled heterogeneity in the mark-recapture component of the data. By modelling the covariance in detection probabilities with distance, we show how the estimation problem can be formulated in terms of different levels of independence. At one extreme, full independence is assumed, as in the Petersen estimator (which does not use distance data); at the other extreme, independence only occurs in the limit as detection probability tends to one. Between the two extremes, there is a range of models, including those currently in common use, which have intermediate levels of independence. We show how this framework can be used to provide more reliable analysis of double-observer line transect data. We test the methods by 1 simulation, and by analysis of a dataset for which true abundance is known. We illustrate the approach through analysis of minke whale sightings data from the North Sea and adjacent waters. Text minke whale Unknown Petersen ENVELOPE(-101.250,-101.250,-71.917,-71.917) |
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English |
topic |
KEY WORDS Distance sampling Double-observer methods Full independence Limiting independence Line transect sampling Point independence |
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KEY WORDS Distance sampling Double-observer methods Full independence Limiting independence Line transect sampling Point independence Stephen T. Buckl Jeffrey L. Laake David L. Borchers Double-Observer Line Transect Methods: Levels of Independence |
topic_facet |
KEY WORDS Distance sampling Double-observer methods Full independence Limiting independence Line transect sampling Point independence |
description |
Double-observer line transect methods are becoming increasingly widespread, especially for the estimation of marine mammal abundance from aerial and shipboard surveys when detection of animals on the line is uncertain. The resulting data supplement conventional distance sampling data with two-sample mark-recapture data. Like conventional mark-recapture data, these have inherent problems for estimating abundance in the presence of heterogeneity. Unlike conventional mark-recapture methods, line transect methods use knowledge of the distribution of a covariate which affects detection probability (namely distance from the transect line) in inference. This knowledge can be used to diagnose unmodelled heterogeneity in the mark-recapture component of the data. By modelling the covariance in detection probabilities with distance, we show how the estimation problem can be formulated in terms of different levels of independence. At one extreme, full independence is assumed, as in the Petersen estimator (which does not use distance data); at the other extreme, independence only occurs in the limit as detection probability tends to one. Between the two extremes, there is a range of models, including those currently in common use, which have intermediate levels of independence. We show how this framework can be used to provide more reliable analysis of double-observer line transect data. We test the methods by 1 simulation, and by analysis of a dataset for which true abundance is known. We illustrate the approach through analysis of minke whale sightings data from the North Sea and adjacent waters. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Stephen T. Buckl Jeffrey L. Laake David L. Borchers |
author_facet |
Stephen T. Buckl Jeffrey L. Laake David L. Borchers |
author_sort |
Stephen T. Buckl |
title |
Double-Observer Line Transect Methods: Levels of Independence |
title_short |
Double-Observer Line Transect Methods: Levels of Independence |
title_full |
Double-Observer Line Transect Methods: Levels of Independence |
title_fullStr |
Double-Observer Line Transect Methods: Levels of Independence |
title_full_unstemmed |
Double-Observer Line Transect Methods: Levels of Independence |
title_sort |
double-observer line transect methods: levels of independence |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.385.5432 http://www.creem.st-and.ac.uk/stb/ms 080447MR levels of independence.pdf |
long_lat |
ENVELOPE(-101.250,-101.250,-71.917,-71.917) |
geographic |
Petersen |
geographic_facet |
Petersen |
genre |
minke whale |
genre_facet |
minke whale |
op_source |
http://www.creem.st-and.ac.uk/stb/ms 080447MR levels of independence.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.385.5432 http://www.creem.st-and.ac.uk/stb/ms 080447MR levels of independence.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
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1766069734821855232 |