sim.gRoeMetz.config {iMRMC}

Create a configuration object for the sim.gRoeMetz program

Description

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.

Usage

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
)

Arguments

nR

Number of readers (default = 5)

nC.neg

Number of signal-absent cases (default = 25)

nC.pos

Number of signal-present cases (default = 25)

mu.neg

Mean fixed effect of signal-absent distribution (default = 0.0)
Modality specific parameters are set to zero: mu.Aneg = mu.Bneg = 0

mu.pos

Mean fixed effect of signal-present distribution (default = 1.0)
Modality specific parameters are set to zero: mu.Apos = mu.Bpos = 0

var_r

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

var_c

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

var_rc

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

Details

If no arguments, this function returns a default simulation configuration for sim.gRoeMetz

Value

config [list] Refer to the sim.gRoeMetz input variable