check_systematic_demand: Check Demand Data for Unsystematic Responding

In beezdemand: Behavioral Economic Easy Demand

Check Demand Data for Unsystematic Responding

Description

Modern interface for screening purchase task data using Stein et al. (2015) criteria. Returns a structured object with standardized output vocabulary that is consistent with check_systematic_cp().

Usage

check_systematic_demand(
  data,
  trend_threshold = 0.025,
  bounce_threshold = 0.1,
  max_reversals = 0,
  consecutive_zeros = 2,
  x_var = "x",
  y_var = "y",
  id_var = "id"
)

Arguments

data	Data frame in long format with columns: id, x (price), y (consumption).
trend_threshold	Numeric. Threshold for trend detection (log-log slope). Default 0.025.
bounce_threshold	Numeric. Threshold for bounce proportion. Default 0.10.
max_reversals	Integer. Maximum allowed reversals from zero. Default 0.
consecutive_zeros	Integer. Consecutive zeros required for reversal detection. Default 2 (per Stein et al. 2015).
x_var	Character. Name of the price column. Default "x".
y_var	Character. Name of the consumption column. Default "y".
id_var	Character. Name of the subject identifier column. Default "id".

Details

The results tibble contains standardized columns for both demand and cross-price systematicity checks:

id

Subject identifier

type

"demand" for this function

trend_stat

DeltaQ statistic (log-log slope)

trend_threshold

Threshold used

trend_direction

"down", "up", or "none"

trend_pass

Logical: passed trend criterion

bounce_stat

Bounce proportion

bounce_threshold

Threshold used

bounce_direction

"significant" or "none"

bounce_pass

Logical: passed bounce criterion

reversals

Count of reversals from zero

reversals_pass

Logical: passed reversals criterion

returns

NA for demand (CP-specific)

n_positive

Count of positive values

systematic

Logical: passed all criteria

Value

An object of class beezdemand_systematicity with components:

results

Tibble with one row per subject containing systematicity metrics

type

"demand"

call

The original function call

n_total

Total number of subjects

n_systematic

Number of subjects passing all criteria

n_unsystematic

Number of subjects failing at least one criterion

Examples

data(apt)
check <- check_systematic_demand(apt)
print(check)
summary(check)
tidy(check)

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