eff_size_per_foils {r4lineups}

Effective Size per Foils

Description

Function for computing effective size (Malpass, 1981) counting foils who fall within the CI for chance guessing

Usage

eff_size_per_foils(lineup_vec, target_pos, k, conf = 0.95)

Arguments

lineup_vec

A numeric vector of lineup choices

target_pos

A numeric vector indexing all lineup members

k

Number of members in lineup. Must be specified by user (scalar).

conf

Desired level of alpha. Defaults to 0.95. May be specified by user (scalar).

References

Malpass, R S. (1981). Effective size and defendant bias in eyewitness identification lineups. Law and Human Behavior, 5, 299-309.

Tredoux, C. G. (1998). Statistical inference on measures of lineup fairness. Law and Human Behavior, 22(2), 217-237.

Examples

#Data:
lineup_vec <- round(runif(100, 1, 6))
target_pos <- c(1, 2, 3, 4, 5, 6)

#Call:
eff_size_per_foils(lineup_vec, target_pos, 6)
eff_size_per_foils(lineup_vec, target_pos, conf = 0.95, 6)