). This array is often used in a RSM to construct a response surface. For each factor are 3 levels required.
Box-Behnken compared with Central Composite
As you can see there are less data point needed compared with a Central Composite design. Compared to the Central Composite design it is missing the corner points, it will never occur that all the factors are high or low at the same time (No extreme combinations).
With a Box-Behnken design every factor is having 3 levels compared to Central Composite 5 with 2 of them outside the setting.