redesign quickly generates a design from an existing one by resetting symbols used in design handler parameters in a step's environment (Advanced).
redesign(design, ..., expand = TRUE)
An object of class design.
Arguments to redesign e.g.,
n = 100. If redesigning multiple arguments, they must be specified as a named list.
If TRUE, redesign using the crossproduct of
..., otherwise recycle them.
A design, or, in the case of multiple values being passed onto
..., a `by`-list of designs.
redesign will edit any symbol in your design, but if the symbol you attempt to change does not exist in a step's environment no changes will be made and no error or warning will be issued.
Please note that
redesign functionality is experimental and may be changed in future versions.
n <- 500 population <- declare_model(N = 1000) sampling <- declare_sampling(S = complete_rs(N, n = n), legacy = FALSE) design <- population + sampling # returns a single, modified design modified_design <- redesign(design, n = 200) # returns a list of six modified designs design_vary_N <- redesign(design, n = seq(400, 900, 100)) # When redesigning with arguments that are vectors, # use list() in redesign, with each list item # representing a design you wish to create prob_each <- c(.1, .5, .4) assignment <- declare_assignment( Z = complete_ra(prob_each = prob_each), legacy = FALSE) design <- population + assignment # returns two designs designs_vary_prob_each <- redesign( design, prob_each = list(c(.2, .5, .3), c(0, .5, .5))) # To illustrate what does and does not get edited by redesign, # consider the following three designs. In the first two, argument # X is called from the step's environment; in the third it is not. # Using redesign will alter the role of X in the first two designs # but not the third one. X <- 3 f <- function(b, X) b*X g <- function(b) b*X design1 <- declare_model(N = 1, A = X) + NULL design2 <- declare_model(N = 1, A = f(2, X)) + NULL design3 <- declare_model(N = 1, A = g(2)) + NULL draw_data(design1) #> ID A #> 1 1 3 draw_data(design2) #> ID A #> 1 1 6 draw_data(design3) #> ID A #> 1 1 6 draw_data(redesign(design1, X=0)) #> ID A #> 1 1 0 draw_data(redesign(design2, X=0)) #> ID A #> 1 1 0 draw_data(redesign(design3, X=0)) #> ID A #> 1 1 6