Question

In case of Completely randomized design (CRD) which of the following statement is false?

• A. CRD is flexible design in the sense that, any treatment can have any number of replications
• B. CRD provides least degree of freedom to estimate experimental error
• C. Principle of local control is not applicable for CRD
• D. CRD is mainly applicable for lab experiments

Hint:

Remember that CRD actually provides the maximum degrees of freedom for estimating experimental error, which makes it highly sensitive when experimental units are perfectly homogeneous.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Completely Randomized Design (CRD) is the simplest of all experimental designs, where treatments are assigned to experimental units completely at random.

Step 2: Detailed Explanation:
Let us evaluate each statement to determine its truth value:
- (A) "CRD is flexible in the sense that any treatment can have any number of replications": This is true. Unlike other designs, CRD easily accommodates unequal replication numbers across treatments.
- (B) "CRD provides least degree of freedom to estimate experimental error": This is false. Since CRD does not use blocking or grouping, no degrees of freedom are lost to blocks. Thus, the error degrees of freedom ($N-v$) are maximized under CRD compared to blocked designs like RCBD ($N-v-r+1$).
- (C) "Principle of local control is not applicable for CRD": This is true. CRD uses only two basic principles of experimental design: replication and randomization.
- (D) "CRD is mainly applicable for lab experiments": This is true because laboratory, greenhouse, and pot experiments are conducted under highly controlled, homogeneous environments.
Therefore, statement (B) is the false statement.

Step 3: Final Answer
The correct option is (B).