Key Concepts in Experimental Design for AP Stats

Which of the following is NOT one of the four major aspects of a good experimental design?

• Comparison

• Observation

• Randomization

• Replication

What is the primary difference between an observational study and an experiment?

• Observational studies involve randomization.

• Experiments allow researchers to show a cause-and-effect relationship.

• Observational studies require a control group.

• Experiments do not involve any form of control.

Why is randomization important in an experiment?

• It allows for the use of a placebo.

• It guarantees that the results will be significant.

• It helps in eliminating bias in assigning treatments.

• It ensures that the sample size is large.

What does replication in an experiment refer to?

• Ensuring that the experiment is double-blind.

• Repeating the experiment with a larger sample size.

• Randomly assigning subjects to different groups.

• Using a placebo in the control group.

How can researchers control for the placebo effect?

• By ensuring all subjects think they are receiving a treatment.

• By not informing subjects about the experiment.

• By giving all subjects a placebo.

• By using only non-human subjects.

What is a single-blind experiment?

• An experiment where only the evaluators do not know which treatment the subjects are receiving.

• An experiment where neither subjects nor evaluators know the treatments.

• An experiment where both subjects and evaluators know the treatments.

• An experiment where only the subjects do not know which treatment they are receiving.

In a completely randomized design, how are subjects assigned to groups?

• Based on their characteristics.

• By assigning them to groups based on their preferences.

• Randomly, without considering their characteristics.

• By allowing subjects to choose their groups.

What is the purpose of a randomized block design?

• To randomly assign subjects to treatments without any grouping.

• To eliminate the need for a control group.

• To control for a confounding variable by separating subjects into blocks.

• To ensure that each group has an equal number of subjects.

In a matched pair design, what is the main criterion for pairing subjects?

• Subjects are paired based on their availability.

• Subjects are paired randomly.

• Subjects are paired based on their preferences.

• Subjects are paired based on their similarities.

Which of the following is an advantage of using a block design in an experiment?

• It increases the sample size.

• It reduces variation within groups.

• It eliminates the need for randomization.

• It ensures that all subjects receive the same treatment.