Design Matrices for Multiple Membership Models

Forms design matrices for multiple membership models

Usage

mult.memb(formula)

Arguments

formula

formula

Value

design matrix

Author

Jarrod Hadfield j.hadfield@ed.ac.uk

Details

Currently mult.memb can only usefully be used inside an idv variance function. The formula usually contains serveral factors that have the same factor levels.

Examples

fac1<-factor(sample(letters[1:3], 5, TRUE), levels=letters[1:3])
fac2<-factor(sample(letters[1:3], 5, TRUE), levels=letters[1:3])
cbind(fac1, fac2)
#>      fac1 fac2
#> [1,]    2    2
#> [2,]    3    1
#> [3,]    1    2
#> [4,]    3    3
#> [5,]    2    3
mult.memb(~fac1+fac2)
#>   fac1a fac1b fac1c
#> 1     0     2     0
#> 2     1     0     1
#> 3     1     1     0
#> 4     0     0     2
#> 5     0     1     1
#> attr(,"assign")
#> [1] 1 1 1
#> attr(,"contrasts")
#> attr(,"contrasts")$fac1
#> [1] "contr.treatment"
#>