3. Experimental testing of the plan and collection of responses y

For each experiment in the design, the levels of the various factors are finally converted back into the real unit u _i so that the tests can be carried out on a practical level. For example, in the case of the first experiment in the X matrix, the X ₁ variable associated with temperature must be adjusted to level -1, which corresponds to a setpoint equal to 24°C ( see figure Area of study of the temperature factor of a CLHPX ₁ furnace as part of a robustness study).

Once all the experiments in the design have been carried out in practice, and the corresponding responses y _i have been measured, the respective effect of each factor on the response is calculated using the box formula...