effect

Given the first two probabilities of a trinomial distribution
before and after a change, <code>effect()</code> adds an arrow to an existing
ternary plot. If the probability distribution does not change, a
point (instead of an arrow) is added to the plot.

internal

An implementation of the ternary plot for interpreting regression
coefficients of trinomial regression models, as proposed in Santi, Dickson
and Espa (2019) <doi:10.1080/00031305.2018.1442368>. Ternary plots can be
drawn using either 'ggtern' package (based on 'ggplot2') or 'Ternary'
package (based on standard graphics). The package and its features are
illustrated in Santi, Dickson, Espa and Giuliani (2022)
<doi:10.18637/jss.v103.c01>.

Flavio Santi

plot3logit

Ternary Plots for Trinomial Regression Models

Maria Michela Dickson

Giuseppe Espa

Diego Giuliani

effect function

<dl><dt>x, y</dt>
<dd><code>numeric</code> vectors of the first two probabilities. If
the probability distribution is unchanged, <code>x</code> and <code>y</code> should
have length one.</dd>
<dt>...</dt>
<dd>other graphical parameters such as <code>xpd</code> and the line
characteristics <code>lend</code>, <code>ljoin</code> and <code>lmitre</code>. See
<code><a href="/link/graphics%3A%3Apar()?package=plot3logit&version=3.2.0" data-mini-rdoc="plot3logit::graphics::par()">graphics::par()</a></code>.</dd>
<dt>length</dt>
<dd>length of the edges of the arrow head (in inches).</dd></dl>

Arguments

Only when <code>effect()</code> is passed to <code>Ternary::AddToTernary()</code>
as the first argument, arrows and points are drawn consistently
with ternary coordinate system, otherwise <code>effect</code> draws both
arrows and points according to a Cartesian coorinate system
centered on \((0,0.5,0.5)\).

Warning

Draw a change in the probability distribution on an existing plot — effect

<dl>

<dt>x, y</dt>
<dd><code>numeric</code> vectors of the first two probabilities. If
the probability distribution is unchanged, <code>x</code> and <code>y</code> should
have length one.</dd>


<dt>...</dt>
<dd>other graphical parameters such as <code>xpd</code> and the line
characteristics <code>lend</code>, <code>ljoin</code> and <code>lmitre</code>. See
<code><a href='https://rdrr.io/r/graphics/par.html'>graphics::par()</a></code>.</dd>


<dt>length</dt>
<dd>length of the edges of the arrow head (in inches).</dd>

</dl>

Only when <code>effect()</code> is passed to <code>Ternary::AddToTernary()</code>
as the first argument, arrows and points are drawn consistently
with ternary coordinate system, otherwise <code>effect</code> draws both
arrows and points according to a Cartesian coorinate system
centered on \((0,0.5,0.5)\).

effect: Draw a change in the probability distribution on an existing plot

Description

Usage

Arguments

Warning