I have designed a screening experiment assigning some numerical columns to be continuous.
The experiments have been run and I need some supplementary runs however I would like these columns to be discrete numbers.
I am struggling to find a way to include the already existing runs in this new design.
Typically, starting with 4 continuous variables and the 8 runs of a half-fractional experiment, how to generate a design including these runs when 2 of these 4 variables can only take specific values (respectively 3 and 4 levels). The new design is looking at all main effects, secondary interactions, quadratic terms (Xi*Xi) and a blocking var to distinguish the initial runs from the new ones.