RCBD: Randomized Complete Block Design

This experimental design contains blocks , and each block has enough experimental units such that all treatments can be measured within the block. This allows block differences to be removed, and treatments compared under the more uniform conditions within a block.

Plant Example: You have 40 pots in a greenhouse, and 4 treatments. The 40 pots are on 10 benches, and each bench may have different light, temperature or moisture conditions that could affect the response variable. Thus each bench will be a BLOCK, and all treatments are randomly assigned to every block. This ensures that all treatments experience the same range of bench conditions.

Animal Example: You have 40 steers, which differ in age and weight such that 10 groups can be formed, with the 4 steers within a group being reasonably similar. Thus the 10 groups are BLOCKS, and all 4 diet treatments are assigned at random to steers within every block.