plot.cp_model_lm: Plot Method for Linear Cross-Price Demand Models

Description

Creates a ggplot2 visualization of a fitted linear cross-price demand model (of class cp_model_lm). The plot overlays a prediction line over the observed data points. Axis transformations (e.g., "log10") can be applied. If the model includes group effects, separate lines will be drawn for each group.

Usage

# S3 method for cp_model_lm
plot(
  x,
  data = NULL,
  inv_fun = identity,
  n_points = 100,
  title = NULL,
  xlab = "Price",
  ylab = "Consumption",
  x_trans = "identity",
  y_trans = "identity",
  point_size = 3,
  ...
)

Value

A ggplot2 object displaying the fitted model predictions and observed data.

Arguments

x: A cp_model_lm object (as returned by fit_cp_linear(type = "fixed", ...)).
data: Optional data frame containing columns x and y to plot. If not provided, the function uses object$data if available.
inv_fun: Optional function to inverse-transform predictions. Default is identity. Not typically used for linear models but included for API consistency.
n_points: Number of points to create in the prediction grid. Default is 100.
title: Optional title for the plot; default is NULL.
xlab: Label for the x-axis. Default is "Price".
ylab: Label for the y-axis. Default is "Consumption".
x_trans: Transformation for the x-axis; one of "identity", "log10", or "pseudo_log". Default is "identity".
y_trans: Transformation for the y-axis; one of "identity", "log10", or "pseudo_log". Default is "identity".
point_size: Size of the data points in the plot. Default is 3.
...: Additional arguments passed to the generic predict method.