DoseFinding (version 0.1-3)

sigEmax: Sigmoid Emax Model

Description

The model function for the sigmoid Emax model is defined as $$f(d,\theta)=E_0+E_{max}\frac{d^h}{ED^h_{50}+d^h}$$

Usage

sigEmax(dose, e0, eMax, ed50, h)

Arguments

dose

Dose variable

e0

Placebo effect

eMax

Asymptotic maximum change from placebo effect

ed50

Dose giving half of the asymptotic maximum effect

h

Hill parameter, determining the steepness of the model at the ED50

Value

• Response value

Details

The sigmoid Emax model is an extension of the (hyperbolic) Emax model by introducing an additional parameter h, that determines the steepness of the curve at the ed50 value. The sigmoid Emax model describes monotonic, sigmoid dose-response relationships.

References

MacDougall, J. (2006). Analysis of dose-response studies - Emax model,in N. Ting (ed.), Dose Finding in Drug Development, Springer, New York, pp. 127--145

See Also

emax, logistic, betaMod, linlog, linear, quadratic, exponential

Examples

## some example shapes
sigEmaxModList <- list(sigEmax = rbind(c(0.5,1), c(0.5,8), c(0.2,1), c(0.2,8)))
plotModels(sigEmaxModList, c(0,1), base = 0, maxEff = 1)