Question

Select the definition of a block design experiment.

A)a study in which subjects are separated into similar groups and then subjects within each group are randomly assigned to treatments
B)a study in which all subjects are randomly assigned to treatment groups, allowing for comparison of those treatments
C)a study in which one subject receives two treatments in random order
D)a study in which subjects are randomly assigned to treatment groups and each treatment group is further divided into groups containing similar individuals
E)a study in which researchers divide subjects into similar groups and observe variables of interest within each group

Answer 1

A block design experiment is a study where subjects are divided into similar groups, followed by random assignment to treatments, which allows any observed differences in outcomes to be confidently attributed to the treatment effects.

Step-by-step explanation:

The definition of a block design experiment is answer choice A): a study in which subjects are separated into similar groups and then subjects within each group are randomly assigned to treatments. This ensures that all potential lurking variables are spread equally among the groups, which means any differences observed in the outcome must be a result of the treatment and not due to variability within the subjects. Random assignment is a crucial factor of such experimental designs, which makes sure that the only difference between groups is the one imposed by the researcher.