Functions implementing multivariate optimization and ranking using the desirability function approach described in Derringer and Suich (1980)
## Default S3 method:dMax(low, high, scale =1, tol =NULL,...)## Default S3 method:dMin(low, high, scale =1, tol =NULL,...)## Default S3 method:dTarget(low, target, high, lowScale =1, highScale =1, tol =NULL,...)## Default S3 method:dArb(x, d, tol =NULL,...)## Default S3 method:dBox(low, high, tol =NULL,...)## Default S3 method:dCategorical(values, tol =NULL,...)## Default S3 method:dOverall(...)
Arguments
low: a constant to define the desirability function for dMax, dMin, dTarget and dBox
high: a constant to define the desirability function for dMax, dMin, dTarget and dBox
target: a constant to define the desirability function for dMax, dMin, dTarget and dBox
scale: the scaling factor for dMax and dMin. Values less than one make the criteria more difficult to satisfy while values greater than one make it easier.
lowScale: the scaling factor for dTarget. This bends the curve between the points low and target. Values less than one make the criteria more difficult to satisfy while values greater than one make it easier.
highScale: the scaling factor for dTarget. This bends the curve between the points high and target. Values less than one make the criteria more difficult to satisfy while values greater than one make it easier.
x: a set of input values
d: a set of desirabilites between zero and one (inclusive) that match the length of x
values: a named numeric vector of possible values
tol: an optional tolerance for zero desirability. When this is non-null, zero desirabilites are replaced with this value
``: For dOverall, this is one or more desirability objects. For the other methods, this argument is not currently used
Details
The functions dMax, dMin, dTarget ande dOverall are the basic equations used by Derringer and Suich (1980). dBox is a simple step funciton between two points. dArb can be used to create other shapes that do not fall into the other funcional forms. See the package vignette or the references for more details
Returns
a list. Common values are:
tol: the value specified by the tol argument
call: the origianl function call
References
Derringer, G. and Suich, R. (1980), Simultaneous Optimization of Several Response Variables. Journal of Quality Technology 12 , 214--219.