skylark

skylark2

The Skylark dataset that was included with the original TRIM software.
The dataset can be loaded in two forms. The <code>skylark</code> dataset is
exactly equal to the data set in the original TRIM software:
<table class="table">
<tr><td>Column</td><td>Type</td><td>Description</td></tr>
<tr><td><code>site</code></td><td><code>integer</code></td><td>Site number</td></tr>
<tr><td><code>time</code></td><td><code>integer</code></td><td>Time point coded as integer sequence</td></tr>
<tr><td><code>count</code></td><td><code>numeric</code></td><td>Counted skylarks</td></tr>
<tr><td><code>Habitat</code></td><td><code>integer</code></td><td>Habitat type (1, 2)</td></tr>
<tr><td><code>Deposition</code></td><td><code>integer</code></td><td>Deposition type (1, 2, 3, 4)</td></tr>
</table>
 The current implementation is more flexible and allows time points to be coded as years
and covariates as factors. The <code>skylark2</code> data set looks as follows.
<table class="table">
<tr><td>Column</td><td>Type</td><td>Description</td></tr>
<tr><td><code>site</code></td><td><code>factor</code></td><td>Site number</td></tr>
<tr><td><code>year</code></td><td><code>integer</code></td><td>Time point coded as year</td></tr>
<tr><td><code>count</code></td><td><code>integer</code></td><td>Counted skylarks</td></tr>
<tr><td><code>Habitat</code></td><td><code>factor</code></td><td>Habithat type (<code>dunes</code>, <code>heath</code>)</td></tr>
<tr><td><code>Deposition</code></td><td><code>integer</code></td><td>Deposition type (1, 2, 3, 4)</td></tr>
<tr><td><code>Weight</code></td><td><code>numeric</code></td><td>Site weight</td></tr>
</table>

The TRIM model is widely used for estimating growth and decline of
animal populations based on (possibly sparsely available) count data. The
current package is a reimplementation of the original TRIM software developed
at Statistics Netherlands by Jeroen Pannekoek. See
<https://www.cbs.nl/en-gb/society/nature-and-environment/indices-and-trends%2d%2dtrim%2d%2d>
for more information about TRIM.

Adriaan Meyling

rtrim

Trends and Indices for Monitoring Data

Patrick Bogaart

Mark van der Loo

Jeroen Pannekoek

Statistics Netherlands 

skylark function

Format

The Skylark dataset that was included with the original TRIM software.
The dataset can be loaded in two forms. The <code>skylark</code> dataset is
exactly equal to the data set in the original TRIM software:
<table class='table'>
<tr><td>Column</td><td>Type</td><td>Description</td></tr>
<tr><td><code>site</code></td><td><code>integer</code></td><td>Site number</td></tr>
<tr><td><code>time</code></td><td><code>integer</code></td><td>Time point coded as integer sequence</td></tr>
<tr><td><code>count</code></td><td><code>numeric</code></td><td>Counted skylarks</td></tr>
<tr><td><code>Habitat</code></td><td><code>integer</code></td><td>Habitat type (1, 2)</td></tr>
<tr><td><code>Deposition</code></td><td><code>integer</code></td><td>Deposition type (1, 2, 3, 4)</td></tr>
</table>
 

The current implementation is more flexible and allows time points to be coded as years
and covariates as factors. The <code>skylark2</code> data set looks as follows.
<table class='table'>
<tr><td>Column</td><td>Type</td><td>Description</td></tr>
<tr><td><code>site</code></td><td><code>factor</code></td><td>Site number</td></tr>
<tr><td><code>year</code></td><td><code>integer</code></td><td>Time point coded as year</td></tr>
<tr><td><code>count</code></td><td><code>integer</code></td><td>Counted skylarks</td></tr>
<tr><td><code>Habitat</code></td><td><code>factor</code></td><td>Habithat type (<code>dunes</code>, <code>heath</code>)</td></tr>
<tr><td><code>Deposition</code></td><td><code>integer</code></td><td>Deposition type (1, 2, 3, 4)</td></tr>
<tr><td><code>Weight</code></td><td><code>numeric</code></td><td>Site weight</td></tr>
</table>

Skylark population data — skylark

Skylark population data

Column	Type	Description
`site`	`integer`	Site number
`time`	`integer`	Time point coded as integer sequence
`count`	`numeric`	Counted skylarks
`Habitat`	`integer`	Habitat type (1, 2)
`Deposition`	`integer`	Deposition type (1, 2, 3, 4)

Column	Type	Description
`site`	`factor`	Site number
`year`	`integer`	Time point coded as year
`count`	`integer`	Counted skylarks
`Habitat`	`factor`	Habithat type (`dunes`, `heath`)
`Deposition`	`integer`	Deposition type (1, 2, 3, 4)
`Weight`	`numeric`	Site weight

skylark: Skylark population data

Description

Usage

Arguments

Format