isobole {drc}

Creating isobolograms

Description

'isobole' displays isobole based on EC/ED50 estimates from a log-logistic model. Additionally isoboles determined by the concentration addition model, Hewlett's model and Voelund's model can be added to the plot.

Usage

isobole(object1, object2, exchange = 1, cifactor = 2, ename = "e", 
xaxis = "100", xlab, ylab, xlim, ylim, ...)

Arguments

object1

object of class 'drc' where EC/ED50 parameters vary freely.

object2

object of class 'drc' where EC/ED50 parameters vary according to Hewlett's model.

ename

character string. The name of the EC/ED50 variable.

xaxis

character string. Is the mixture "0:100" or "100:0" on the x axis?

exchange

numeric. The exchange rate between the two substances.

cifactor

numeric. The factor to be used in the confidence intervals. Default is 2, but 1 has been used in publications.

xlab

an optional label for the x axis.

ylab

an optional label for the y axis.

xlim

a numeric vector of length two, containing the lower and upper limit for the x axis.

ylim

a numeric vector of length two, containing the lower and upper limit for the y axis.

...

Additional graphical parameters.

Details

The model fits to be supplied as first and optionally second argument are obtained using mixture and drm.

Value

No value is returned. Only used for the side effect: the isobologram shown.

Author(s)

Christian Ritz

References

Ritz, C. and Streibig, J. C. (2014) From additivity to synergism - A modelling perspective Synergy, 1, 22–29.

See Also

The examples in acidiq, glymet and mecter.