qualityTools (version 1.31.1)

starDesign: Axial Design

Description

starDesign is a function to create the star portion of a response surface design. The starDesign function can be used to create a star portion of a response surface design for a sequential assembly strategy. One can either specify k and p and alpha and cs and cc OR simply simply pass an object of class facDesign to the data. In the latter an object of class facDesign otherwise a list containing the axial runs and centerpoints is returned.

Usage

starDesign(k, p = 0, alpha = c("both", "rotatable", "orthogonal"), cs, cc, data)

Arguments

k

integer - number of factors

p

integer - number of factors via aliasing

alpha

if no numeric value is given defaults to both i.e. orthogonality and rotatibility

cs

integer - number of centerpoints in the star portion of the design

cc

integer - number of centerpoints in the cube portion of the design

data

optional - an object of class facDesign

Value

• a facDesign object if an object of class facDesign is given or a list containing entries for axial runs and center points in the cube and the star portion of a design

References

Response Surface Methodology (2009) Myers, Montgomery, Anderson-Cook

See Also

facDesign for 2^k factorial designs,fracDesign for 2^k-p fractional factorial designs,rsmDesign for response surface designs, mixDesign for mixture designs or taguchiDesign for taguchi designs

Examples

#Example 1 - sequential assembly
fdo = facDesign(k = 3, centerCube = 1)  #factorial design with one center point in the cube portion
fdo
response(fdo) = 1:9  #set the response via generic response method
rsd = starDesign(data = fdo)  #sequential assembly of a response surface design (rsd)
rsd

#Example 2 - returning a list
starDesign(k = 3, cc = 2, cs = 2, alpha = "orthogonal")
starDesign(k = 3, cc = 2, cs = 2, alpha = "rotatable")
starDesign(k = 3, cc = 2, cs = 2, alpha = "both")