boxplot_subject: Plot interactive boxplots of EEG amplitude across subjects

Description

Function for plotting interactive boxplots of EEG amplitude across subjects for a single epoch and channel, within a specified time interval. The function assumes data from a single epoch and a single sensor. The interactive plotly output enables to easily determine the subjects with outlier amplitude and also allows to easily edit the image layout.

Usage

boxplot_subject(
  data,
  amplitude = "signal",
  subject = NULL,
  time_lim,
  title_label = NULL,
  use_latex = TRUE
)

Value

A plotly object with boxplots of EEG amplitude across subjects.

Arguments

data: A data frame or a database table with EEG dataset. Required columns: subject, sensor, time and the column with EEG amplitude named as in amplitude parameter.
amplitude: A character specifying the name of the column from input data with an EEG amplitude values. Default is "signal".
subject: A vector with IDs of subjects to plot. If missing, boxplots are drawn for all avaliable subjects in data.
time_lim: A numeric vector with time range to plot.
title_label: A character string specifying the title of the plot. Defaults to NULL for plot without title.
use_latex: A logical value indicating whether to use LaTeX formatting for the y-axis title. The default is TRUE.

Details

The input data frame or database table must contain at least following columns: subject - a column with subject IDs, time - a column with time point numbers, and a column with measured EEG signal values (or their averages) called as in amplitude.

Note: The function assumes that subject IDs are unique across the entire dataset. Using the same subject IDs in multiple groups may result in incorrect or misleading visualizations.

Examples

Run this code

# Interactive boxplots of signal from channel E34 in epoch 1
# for both subjects in chosen time points
## Note: it has no statistical sense to make boxplot from only 2 observations, but
## larger example dataset is not possible due to size limit of the package
epochdata |>
pick_data(sensor_rg = "E34", epoch_rg = 1) |>
boxplot_subject(amplitude = "signal", time_lim = c(10:20),
title_label = "Sensor E34, epoch 1")