Question 1

In the context of types of experimental designs, each treatment is administered to a different group of subjects in a _____.

Accepted Answer

In a between-subjects design, each treatment is administered to a different group of subjects. This is in contrast to a within-subjects design, in which each subject receives all of the treatments.

Question 2

In an experiment on the effects of alcohol on memory, participants are first tested after drinking a nonalcoholic beverage and then tested again after drinking an alcoholic beverage. This is an example of a _____ design.

Accepted Answer

This is a within-subjects design because the same participants are tested under both conditions: after drinking a nonalcoholic beverage and after drinking an alcoholic beverage.

Question 3

In a single-subject design, _____.

Accepted Answer

In a single-subject design, each subject is exposed to all levels of an independent variable at different times, data are not averaged across subjects, and reliability is assessed with replication.

Question 4

The statistical variability among scores caused by the influence of variables other than your independent variable is called _____ variance.

Accepted Answer

The answer of The statistical variability among scores caused by...

Question 5

The presence of error variance:

Accepted Answer

Error variance refers to the variability in the data that cannot be attributed to the independent variable, making it difficult to determine the effectiveness of the independent variable.

Question 6

A way of reducing error variance is to:

Accepted Answer

All the options provided are methods to reduce error variance: controlling extraneous variables, randomizing error variance, and increasing the effectiveness of the independent variable.

Question 7

Analysis of your data with inferential statistics:

Accepted Answer

Inferential statistics help determine if the observed effects in your data are due to the independent variable or if they could have occurred by chance due to error variance.

Question 8

In a _____ design, you assign subjects to one of two groups on a purely random basis.

Accepted Answer

In a randomized two-group design, subjects are assigned to one of two groups randomly, ensuring that each participant has an equal chance of being placed in either group.

Question 9

An advantage of the randomized two-group design is that it:

Accepted Answer

The randomized two-group design is straightforward to implement and analyze, making it a practical choice for many experiments.

Question 10

A drawback of the randomized two-group design is that it:

Accepted Answer

The randomized two-group design is simple and provides limited information about the effect of an independent variable because it only compares two groups, which may not capture the full complexity of the variable's impact.

Question 11

Dr. Jones conducts a randomized two-group experiment on the effect of a drug on learning. She finds that subjects who receive the drug score more poorly on a memory test than those who do not receive the drug. Which of the following would Dr. Jones be justified in concluding?

Accepted Answer

Dr. Jones can conclude that the drug affects memory test scores, but without further analysis, it is speculative to determine the exact nature of the relationship (linear, curvilinear, etc.).

Question 12

An experimental design with more than two levels of a single independent variable is called a _____ design.

Accepted Answer

A single-factor multigroup design involves more than two levels of a single independent variable.

Question 13

When you manipulate your independent variable quantitatively, you are using a _____.

Accepted Answer

A parametric design involves manipulating the independent variable quantitatively to observe changes in the dependent variable.

Question 14

If you vary the quantity of a drug administered to subjects by using 10 mg, 20 mg, and 40 mg, you are using a _____ design.

Accepted Answer

A parametric design involves varying the levels of a single independent variable, such as the dosage of a drug, to observe its effects.

Question 15

Manipulating your independent variable qualitatively results in a _____.

Accepted Answer

Manipulating the independent variable qualitatively involves using non-numeric categories or groups, which aligns with a nonparametric design.

Question 16

Often in studies that look at the effects of drugs on behavior, it is found that a participant's behavior can be altered if he or she believes a drug was taken. To test for this possibility, you would use a:

Accepted Answer

A multiple control group design allows for the inclusion of a placebo group, which helps determine if changes in behavior are due to the belief of taking a drug rather than the drug itself.

Question 17

In an experiment designed to study the effects of a drug on behavior, participants in the control group received a sugar pill rather than either the active drug or no drug. These participants constitute a:

Accepted Answer

A placebo control group is used to compare the effects of the active drug against a group that receives an inactive substance, like a sugar pill, to account for the placebo effect.

Question 18

A design including a placebo control group is used to detect:

Accepted Answer

A placebo control group is used to detect the effect of a participant's belief that they have received a drug, which helps differentiate between the actual effects of the drug and the psychological effects of believing one has taken the drug.

Question 19

The matched-groups design is most useful when:

Accepted Answer

The matched-groups design is used to control for subject characteristics that might influence the dependent variable by matching participants on those characteristics, ensuring they are equally distributed across groups.

Question 20

In a matched-groups design, after selecting a sample of subjects, you:

Accepted Answer

In a matched-groups design, subjects are paired based on a specific characteristic, and then one member of each pair is randomly assigned to different groups to ensure that the groups are equivalent on that characteristic.

Quiz 10: Using Between-Subjects and Within-Subjects Experimental Designs