covtheta

Estimates var/cov matrix of inflation factors (1/prob detection) using a
non-parametric bootstrap. Called by function Sight.Est if Vm.boot = TRUE.

methods

Uses logistic regression to model the probability of detection as a function of covariates.
This model is then used with observational survey data to estimate population size, while
accounting for uncertain detection.  See Steinhorst and Samuel (1989).

Carl Schwarz

SightabilityModel

Wildlife Sightability Modeling

Fieberg John

Schwarz Carl James

covtheta function

<dl><dt>total</dt>
<dd>Number of animals in each independently sighted group</dd>
<dt>srates</dt>
<dd>Plot sampling probability (associated with the independently
observed animal groups)</dd>
<dt>stratum</dt>
<dd>Stratum identifiers (associated with the independently
observed animal groups)</dd>
<dt>subunit</dt>
<dd>Plot ID (associated with the independently observed animal
groups)</dd>
<dt>covars</dt>
<dd>Matrix of sightability covariates (associated with the
independently observed animal groups)</dd>
<dt>betas</dt>
<dd>Logistic regression parameter estimates (from fitted
sightability model)</dd>
<dt>varbetas</dt>
<dd>Estimated variance-covariance matrix for the logistic
regression parameter estimates (from fitted sightability model)</dd>
<dt>nboots</dt>
<dd>Number of bootstrap resamples.</dd></dl>

Arguments

Author

Estimates var/cov matrix of inflation factors (1/prob detection) using a
non-parametric bootstrap. — covtheta

<dl>

<dt>total</dt>
<dd>Number of animals in each independently sighted group</dd>


<dt>srates</dt>
<dd>Plot sampling probability (associated with the independently
observed animal groups)</dd>


<dt>stratum</dt>
<dd>Stratum identifiers (associated with the independently
observed animal groups)</dd>


<dt>subunit</dt>
<dd>Plot ID (associated with the independently observed animal
groups)</dd>


<dt>covars</dt>
<dd>Matrix of sightability covariates (associated with the
independently observed animal groups)</dd>


<dt>betas</dt>
<dd>Logistic regression parameter estimates (from fitted
sightability model)</dd>


<dt>varbetas</dt>
<dd>Estimated variance-covariance matrix for the logistic
regression parameter estimates (from fitted sightability model)</dd>


<dt>nboots</dt>
<dd>Number of bootstrap resamples.</dd>

</dl>

covtheta: Estimates var/cov matrix of inflation factors (1/prob detection) using a non-parametric bootstrap.

Description

Usage

Value

Arguments

Author

See Also