In this page, we discuss the reasons for using randomised blocks when designing an experiment to compare several treatments.
Goal of reducing unexplained variability
Amino acid uptake by fish
Intentional variability in the experimental units
Even for experiments in which it is possible to use very similar experimental units, it is not always desireable to do so. If all experimental units are identical, it is difficult to generalise the results to other kinds of experimental units.
Using a variety of different experimental units (grouped into blocks) allows results to be generalised more easily — we can be more confident that the results will hold for a variety of different types of experimental unit.
Penicillin production