plot_interaction_surface

Visualizes a metric (e.g., assurance) as a function of two effect grid variables
for a fixed sample size or averaged over n. Allows line, heatmap, or contour modes.

Provides tools for Bayesian power analysis and assurance calculations using the statistical frameworks of 'brms' and 'INLA'. Includes simulation-based approaches, support for multiple decision rules (direction, threshold, ROPE), sequential designs, and visualisation helpers. Methods are based on Kruschke (2014, ISBN:9780124058880) "Doing Bayesian Data Analysis: A Tutorial with R, JAGS, and Stan", O'Hagan & Stevens (2001) <doi:10.1177/0272989X0102100307> "Bayesian Assessment of Sample Size for Clinical Trials of Cost-Effectiveness", Kruschke (2018) <doi:10.1177/2515245918771304> "Rejecting or Accepting Parameter Values in Bayesian Estimation", Rue et al. (2009) <doi:10.1111/j.1467-9868.2008.00700.x> "Approximate Bayesian inference for latent Gaussian models by using integrated nested Laplace approximations", and Bürkner (2017) <doi:10.18637/jss.v080.i01> "brms: An R Package for Bayesian Multilevel Models using Stan".

Tony Myers

powerbrmsINLA

Bayesian Power Analysis Using 'brms' and 'INLA'

plot_interaction_surface function

<dl><dt>data</dt>
<dd>Data frame (typically power_results$summary).</dd>
<dt>metric</dt>
<dd>Name of the summary column to plot, e.g. "power_direction", "power_threshold".</dd>
<dt>effect1</dt>
<dd>Name of effect grid column for x-axis.</dd>
<dt>effect2</dt>
<dd>Name of effect grid column for y-axis or color/facets.</dd>
<dt>n</dt>
<dd>Optional sample size to filter to (else averages/plots all n's).</dd>
<dt>line</dt>
<dd>Logical; if TRUE, make a lineplot (effect1 on x, one line for each effect2).
If FALSE, make a heatmap or contour.</dd>
<dt>facet_by</dt>
<dd>Optional grid column(s) to facet by.</dd>
<dt>agg_fun</dt>
<dd>Aggregation function if multiple entries per cell (default = mean).</dd>
<dt>title, subtitle</dt>
<dd>Optional plot labels.</dd></dl>

Arguments

Plot Interaction Assurance Surface/Heatmap/Lines (Multi-Effect Grid Friendly) — plot_interaction_surface

<dl>

<dt>data</dt>
<dd>Data frame (typically power_results$summary).</dd>


<dt>metric</dt>
<dd>Name of the summary column to plot, e.g. "power_direction", "power_threshold".</dd>


<dt>effect1</dt>
<dd>Name of effect grid column for x-axis.</dd>


<dt>effect2</dt>
<dd>Name of effect grid column for y-axis or color/facets.</dd>


<dt>n</dt>
<dd>Optional sample size to filter to (else averages/plots all n's).</dd>


<dt>line</dt>
<dd>Logical; if TRUE, make a lineplot (effect1 on x, one line for each effect2).
If FALSE, make a heatmap or contour.</dd>


<dt>facet_by</dt>
<dd>Optional grid column(s) to facet by.</dd>


<dt>agg_fun</dt>
<dd>Aggregation function if multiple entries per cell (default = mean).</dd>


<dt>title, subtitle</dt>
<dd>Optional plot labels.</dd>

</dl>

plot_interaction_surface: Plot Interaction Assurance Surface/Heatmap/Lines (Multi-Effect Grid Friendly)

Description

Usage

Value

Arguments