FAQ/sigdetinR62015-04-20 08:26:50PeterWatson52015-04-14 15:26:03PeterWatson42015-04-14 15:25:23PeterWatson32015-04-14 15:20:48PeterWatson22015-04-14 15:19:50PeterWatson12015-04-14 15:18:57PeterWatsonUsing R to compute A (aprime) and b diagnostics in Zhang, J., & Mueller, S. T. (2005) for evaluating ROC diagnostics nonparametrically(Copied from the weblink) =.5)
{
a <- .75 + (h-f)/4 - f*(1-h)
} else if(f<=h & h<=.5)
{
a <- .75 + (h-f)/4 - f/(4*h)
} else {
a <- .75 + (h-f)/4 - (1-h)/(4 * (1-f))
}
return(a)
}
]]>=.5)
{
b <-(5-4*h)/(1+4*f)
} else if(f<=h & h<=.5)
{
b <-(h^2+h)/(h^2+f)
} else {
b <- ((1-f)^2 + (1-h))/((1-f)^2 + (1-f))
}
return(b)
}]]>Reference Zhang, J., & Mueller, S. T. (2005). A note on ROC analysis and non-parametric estimate of sensitivity. Psychometrika, 70(1), 203–212. doi:10.1007/s11336-003-1119-8