power_curve

<code>plot_power()</code> can be used to visualize the power of a study as a
function of the sampling effort. The power curve plot shows that the
power of the study increases as the sample size increases, and the density
plot shows the overlapping areas where \(\alpha\) and \(\beta\) are
significant.

internal

A system for calculating the optimal sampling effort, based on the ideas of
"Ecological cost-benefit optimization" as developed by A. Underwood (1997,
ISBN 0 521 55696 1). Data is obtained from simulated ecological communities with
prep_data() which formats and arranges the initial data, and then the
optimization follows the following procedure of four functions: (1) prep_data()
takes the original dataset and creates simulated sets that can be used as a
basis for estimating statistical power and type II error. (2) sim_beta() is used
to estimate the statistical power for the different sampling efforts specified
by the user. (3) sim_cbo() calculates then the optimal sampling effort, based
on the statistical power and the sampling costs. Additionally, (4) scompvar()
calculates the variation components necessary for (5) Underwood_cbo() to calculate
the optimal combination of number of sites and samples depending on either
an economic budget or on a desired statistical accuracy. Lastly, (6) plot_power()
helps the user visualize the results of sim_beta().

Arturo Sanchez-Porras

ecocbo

Calculating Optimum Sampling Effort in Community Ecology

Edlin Guerra-Castro

power_curve function

<dl><dt>powr</dt>
<dd>Part of the object of class "ecocbo_beta" that results from
<code>sim_beta()</code>.</dd>
<dt>m</dt>
<dd>Calculated in <code>plot_power()</code>. When using the <code>single.factor</code> model,
m is <code>NULL</code>.</dd>
<dt>n</dt>
<dd>Calculated in <code>plot_power()</code>.</dd>
<dt>cVar</dt>
<dd>Calculated variation components.</dd>
<dt>model</dt>
<dd>Model used for calculating power. Options, so far, are
'single.factor' and 'nested.symmetric'.</dd></dl>

Arguments

Edlin Guerra-Castro (<a href="/link/edlinguerra%40gmail.com?package=ecocbo&version=1.0.0" data-mini-rdoc="ecocbo::edlinguerra@gmail.com">edlinguerra@gmail.com</a>), Arturo Sanchez-Porras

Author

Power curves for different sampling efforts — power_curve

<dl>

<dt>powr</dt>
<dd>Part of the object of class "ecocbo_beta" that results from
<code>sim_beta()</code>.</dd>


<dt>m</dt>
<dd>Calculated in <code>plot_power()</code>. When using the <code>single.factor</code> model,
m is <code>NULL</code>.</dd>


<dt>n</dt>
<dd>Calculated in <code>plot_power()</code>.</dd>


<dt>cVar</dt>
<dd>Calculated variation components.</dd>


<dt>model</dt>
<dd>Model used for calculating power. Options, so far, are
'single.factor' and 'nested.symmetric'.</dd>

</dl>

Edlin Guerra-Castro (<a href='mailto:edlinguerra@gmail.com'>edlinguerra@gmail.com</a>), Arturo Sanchez-Porras

power_curve: Power curves for different sampling efforts

Description

Usage

Value

Arguments

Author

References

See Also