equiv.increase function

Calculate equivalent increase from two dose-response curves

This function takes two curves defined by vectors of x and y values and calculates the equivalent increase in the x value at the response value for the first curve at e1.

equiv.increase(x1, y1, x2, y2, e1, xlog = TRUE)

Arguments

• x1: x vector for first curve
• y1: y vector for first curve
• x2: x vector for second curve
• y2: y vector for second curve
• e1: vector of y responses of first curve for associating with output
• xlog: TRUE if x values are log transformed, changes the output

Details

The function repeatedly uses the approx function to do linear interpolation.

Returns

A list with 5 components - a1: vector of x values associated with e1 from first curve

• e2: vector of y values associated with a1 from the second curve

• a2: vector of x values associated with e2 from the second curve

• e1: input vector for e1

• equiv.increase: vector of equivalent increases associated with e1

Examples

data(deff.sigma)
D<-deff.sigma
equiv.increase(D$mu,D$out1[,2],D$mu,D$out2[,2],.5)