This function creates a configuration object for the Roe & Metz simulation model to be used as input for the sim.gRoeMetz program. The default model returned when there are no arguments given to the function is the "HH" model from Roe1987_Acad-Radiol_v4p298. Following that paper, The user can specify three parameters related to experiment size (nR, nC.neg, nC.pos) and five parameters parameters specifying a linear model that does not depend on modality or truth (mu.neg, mu.pos, var_r, var_c, var_rc). The mu.pos is set to 1.0, which yields a reader averaged AUC of approximately 0.765.
sim.gRoeMetz.config(
nR = 5,
nC.neg = 40,
nC.pos = 40,
mu.neg = 0,
mu.pos = 1,
var_r = 0.03,
var_c = 0.3,
var_rc = 0.2
)config [list] Refer to the sim.gRoeMetz input variable
Number of readers (default = 5)
Number of signal-absent cases (default = 25)
Number of signal-present cases (default = 25)
Mean fixed effect of signal-absent distribution (default = 0.0)
Modality specific parameters are set to zero: mu.Aneg = mu.Bneg = 0
Mean fixed effect of signal-present distribution (default = 1.0)
Modality specific parameters are set to zero: mu.Apos = mu.Bpos = 0
Variance of reader random effect (default = 0.03)
var_r.neg = var_r.pos = var_r.Aneg = var_r.Apos = var_r.Bneg = var_r.Bpos = var_r
Variance of case random effect (default = 0.30)
var_c.neg = var_c.pos = var_c.Aneg = var_c.Apos = var_c.Bneg = var_c.Bpos = var_c
Variance of reader.by.case random effect (default = 0.20)
var_rc.neg = var_rc.pos = var_rc.Aneg = var_rc.Apos = var_rc.Bneg = var_rc.Bpos = var_rc
If no arguments, this function returns a default simulation configuration for sim.gRoeMetz