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Diagnosticity Ratio (Wells & Lindsay, 1980; Wells & Turtle, 1986)

Source: R/diag_ratio_W.R
diag_ratio_W.Rd

Computes Wells' diagnosticity ratio for one lineup pair

Usage

diag_ratio_W(lineup_pres, lineup_abs, pos_pres, pos_abs, k1, k2)

Arguments

lineup_pres

A numeric vector of lineup choices for a lineup in which the target was present

lineup_abs

A numeric vector of lineup choices for a lineup in which the target was absent

pos_pres

A scalar, representing target position in TP lineup. Must be declared by user

pos_abs

A scalar, representing target position in TA lineup. Must be declared by user

k1

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

k2

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

References

Wells, G. L., & Lindsay, R. C. L. (1980).On estimating the diagnosticity of eyewitness nonidentifications.Psychological Bulletin, 88, 776-784.

Wells, G. L., & Turtle, J. W. (1986). Eyewitness identification: The importance of lineup models. Psychological Bulletin, 99, 320-329.

Examples

#Data:
lineup_pres <- round(runif(100, 1, 6))
lineup_abs <- round(runif(70, 1, 5))
pos_pres <- 3
pos_abs <- 5

#Call:
diag_ratio_W(lineup_pres, lineup_abs, pos_pres, pos_abs, 6, 5)
#> [1] 1.6625
diag_ratio_W(lineup_pres, lineup_abs, 3, 5, 6, 5)
#> [1] 1.6625