augment.beezdemand_fixed: Augment a beezdemand_fixed Model with Fitted Values and...

In beezdemand: Behavioral Economic Easy Demand

Augment a beezdemand_fixed Model with Fitted Values and Residuals

Description

Returns the original data with fitted values and residuals from individual demand curve fits. This enables easy model diagnostics and visualization with the tidyverse.

Usage

## S3 method for class 'beezdemand_fixed'
augment(x, newdata = NULL, ...)

Arguments

x	An object of class beezdemand_fixed.
newdata	Optional data frame of new data for prediction. If NULL, uses the original data from the model.
...	Additional arguments (currently unused).

Details

For "hs" equation models where fitting is done on the log10 scale, fitted values are back-transformed to the natural scale.

Value

A tibble containing the original data plus:

.fitted

Fitted demand values on the response scale

.resid

Residuals (observed - fitted)

Examples

data(apt)
fit <- fit_demand_fixed(apt, y_var = "y", x_var = "x", id_var = "id")
augmented <- augment(fit)

# Plot residuals by subject
library(ggplot2)
ggplot(augmented, aes(x = .fitted, y = .resid)) +
  geom_point(alpha = 0.5) +
  facet_wrap(~id) +
  geom_hline(yintercept = 0, linetype = "dashed")

beezdemand documentation built on March 3, 2026, 9:07 a.m.