As I know, full-factorial design can manipulate all the main and interaction effects already. The meaning of fraction factorial design is to reduce the runs based on that some interaction have little effect, such as some high-order interactions.
Why do I need "fracfact" if the runs of "fracfact" is equal or even bigger than the runs of "ff2n"?
Just because "fracfact" can list the columns of interaction?
Excuse me.
As I know, full-factorial design can manipulate all the main and interaction effects already. The meaning of fraction factorial design is to reduce the runs based on that some interaction have little effect, such as some high-order interactions.
Why do I need "fracfact" if the runs of "fracfact" is equal or even bigger than the runs of "ff2n"? Just because "fracfact" can list the columns of interaction?