grtsarea

The sf object containing attributes: id, mdcaty and mdm.

areaframe

Number of points to select in the sample. The default is
100.

samplesize

First number to start siteID numbering. The default is 1.

SiteBegin

Option to randomly shift the hierarchical grid. The
default is TRUE.

shift.grid

Initial number of hierarchical levels to use for the GRTS
grid, which must be less than or equal to maxlev (if maxlev is specified)
and cannot be greater than 11. The default is NULL.

startlev

Maximum number of hierarchical levels to use for the GRTS
grid, which cannot be greater than 11. The default is 11.

maxlev

maxtry

This function select a GRTS sample of an area resource. The function uses
hierarchical randomization to ensure that the sample will include no more
than one point per cell and then picks a point in selected cells.

survey

These functions provide procedures for selecting sites for spatial
surveys using spatially balanced algorithms applied to discrete points,
linear networks, or polygons. The probability survey designs available
include independent random samples, stratified random samples, and unequal
probability random samples (categorical or probability proportional to
size). Design-based estimation based on the results from surveys is
available for estimating totals, means, quantiles, CDFs, and linear models.
The analyses rely on package survey for most results. Variance estimation
options include a local neighborhood variance estimator that is appropriate
for spatially-balanced survey designs. A reference for the survey design
portion of the package is: D. L. Stevens, Jr. and A. R. Olsen (2004),
"Spatially-balanced sampling of natural resources.", Journal of the American
Statistical Association 99(465): 262-278, <DOI:10.1198/016214504000000250>.
Additional helpful references for this package are A. R. Olsen, T. M.
Kincaid, and Q. Payton (2012) and T. M. Kincaid and A. R. Olsen (2012), both
of which are chapters in the book "Design and Analysis of Long-Term
Ecological Monitoring Studies" (R. A. Gitzen, J. J. Millspaugh, A. B.
Cooper, and D. S. Licht (eds.), Cambridge University Press, New York,
<Online ISBN:9781139022422>).

Marc Weber

spsurvey

Spatial Survey Design and Analysis

Tom Kincaid

Tony Olsen

Don Stevens

Christian Platt

Denis White

Richard Remington

grtsarea function

<dl class="dl-horizontal">
 <dt><code>numLevels</code></dt><dd>determines the number of levels for hierarchical
 randomization</dd>
 <dt><code>constructAddr</code></dt><dd>constructs the hierarchical address for
 sample points</dd>
 <dt><code>ranho</code></dt><dd>constructs the randomized hierarchical address for
 sample points</dd>
 <dt><code>pickGridCells</code></dt><dd>selects grid cells that get a sample point</dd>
 <dt><code>insideAreaGridCell</code></dt><dd>determines feature ID value and
 clipped polygon area for each feature contained in a selected grid
 cell</dd>
 <dt><code><a rd-options="" href="/link/selectFeatureID?package=spsurvey&version=4.1.0" data-mini-rdoc="spsurvey::selectFeatureID">selectFeatureID</a></code></dt><dd>identifies a feature ID from which
 to select a sample point</dd>
 <dt><code>pickSamplePoints</code></dt><dd>selects sample points from an sf object</dd>
 </dl>

grtsarea: Select a Generalized Random-Tesselation Stratified (GRTS) Sample of an Area Resource

Description

Usage

Arguments

Value

Other Functions Required