A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates'

Researchers frequently compare rates of change based on counts (e.g. mortality, germination, infection, recruitment). The estimation of mortality and recruitment rates from tree census data have been discussed elsewhere. However, rather than estimating absolute rates, researchers may often need to d...

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Detalles Bibliográficos
Autor principal: Sheil, Douglas
Formato: Journal Article
Lenguaje:Inglés
Publicado: 1999
Materias:
Acceso en línea:https://hdl.handle.net/10568/17916
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author Sheil, Douglas
author_browse Sheil, Douglas
author_facet Sheil, Douglas
author_sort Sheil, Douglas
collection Repository of Agricultural Research Outputs (CGSpace)
description Researchers frequently compare rates of change based on counts (e.g. mortality, germination, infection, recruitment). The estimation of mortality and recruitment rates from tree census data have been discussed elsewhere. However, rather than estimating absolute rates, researchers may often need to determine whether two rates are significantly different. Most biometric texts and computer packages are not very helpful on this question, and guidance is not readily sifted out of the more technical literature. This note is intended to address three related issues: 1) to inform researchers who are not familiar with the appropriate tests, 2) to present an approach that avoids analytical complexity, and 3) to provide some feel for the power of the tests. This third point should assist in experimental design by providing guidance on the sample-sizes and differences required for significance to be detected. The simple and accurate graphical models provided will be of use to biologists who work with count-based changes. The number of observations required to detect significant rate differences may surprise some researchers.
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spelling CGSpace179162025-01-24T14:20:10Z A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates' Sheil, Douglas change forest trees mortality germination diseases recruitment Researchers frequently compare rates of change based on counts (e.g. mortality, germination, infection, recruitment). The estimation of mortality and recruitment rates from tree census data have been discussed elsewhere. However, rather than estimating absolute rates, researchers may often need to determine whether two rates are significantly different. Most biometric texts and computer packages are not very helpful on this question, and guidance is not readily sifted out of the more technical literature. This note is intended to address three related issues: 1) to inform researchers who are not familiar with the appropriate tests, 2) to present an approach that avoids analytical complexity, and 3) to provide some feel for the power of the tests. This third point should assist in experimental design by providing guidance on the sample-sizes and differences required for significance to be detected. The simple and accurate graphical models provided will be of use to biologists who work with count-based changes. The number of observations required to detect significant rate differences may surprise some researchers. 1999 2012-06-04T09:04:44Z 2012-06-04T09:04:44Z Journal Article https://hdl.handle.net/10568/17916 en Sheil, D. 1999. A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates' . Journal of Tropical Forest Science 11 (1) :323-325.
spellingShingle change
forest trees
mortality
germination
diseases
recruitment
Sheil, Douglas
A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates'
title A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates'
title_full A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates'
title_fullStr A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates'
title_full_unstemmed A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates'
title_short A simple graphical method for the comparisons of mortality, recruitment and other count defined 'event-rates'
title_sort simple graphical method for the comparisons of mortality recruitment and other count defined event rates
topic change
forest trees
mortality
germination
diseases
recruitment
url https://hdl.handle.net/10568/17916
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