Hi @AHM,
Welcome in the Community !
Regarding the treatments you would like to have, why not considering a DoE with two factors :
- X1 : Quantity of NPK (with levels at 0 and at "normal/standard" quantity), numeric continuous factor
- X2 : Quantity of new fertilizer (with levels at 0, middle level and high level), numeric continuous factor.
Using a standard factorial approach, and specifying a model with the two main effects, a quadratic effect for X2 to have experimental runs with 3 possible levels ( if you want to have 4 levels for factor X2 : absence, low, middle and high levels you can specify a cubic order effect term in addition in the model) and the interaction between these two factors, you should have all the treatments you are expecting :
You can create this Custom Design with this script (you can modify the quantity levels used, I just used them for illustration):
DOE(
Custom Design,
{Add Response( Maximize, "Y", ., ., . ),
Add Factor( Continuous, 0, 5, "NPK Quantity", 0 ),
Add Factor( Continuous, 0, 10, "New fertilizer quantity", 0 ),
Set Random Seed( 14871954 ), Number of Starts( 312796 ), Add Term( {1, 0} ),
Add Term( {1, 1} ), Add Term( {2, 1} ), Add Term( {2, 2} ),
Add Alias Term( {1, 1}, {2, 1} ), Set Sample Size( 8 ), Simulate Responses( 0 ),
Save X Matrix( 0 ), Make Design}
)
And datatable of the DoE (without replicates) is attached.
If you want to replicate the whole design 2 more times, you can use the "Augment Design" platform (in menu "DoE", "Augment Design"), click on "Replicate" option and specify 3 as the number of replicates :
You'll end up with a completely randomized design with 3 replicates, for a total of 24 runs (datatable attached).
If you have constraints about number of runs done per day for example, you can use blocks in the initial design generation, by adding a factor (type blocking) and specify the number of runs per block :
You can then specify the same model as before (with added block effect), the number of runs in total (24), and you'll end up with a design in 3 blocks (see datatable attached).
I hope these design options may help you in the creation of your DoE,
Victor GUILLER
L'Oréal Data & Analytics
"It is not unusual for a well-designed experiment to analyze itself" (Box, Hunter and Hunter)