Question 1

A professor wanted to examine the effects of diet on learning. He put some laboratory rats on a starvation diet (Group A)but eliminated only desserts from the diet of a second group (Group B). During the experiment, the professor discovered that he needed more Group B rats, so he caught some in a local alley. The results of the experiment showed that Group B rats were faster at learning a maze, so the professor concluded that diet is related to learning speed. Which of the following statements is the most accurate?

Accepted Answer

The professor's conclusion is incorrect because introducing rats from a local alley into Group B introduces a confounding variable, as these rats may have different characteristics affecting learning speed, unrelated to diet.

Question 2

In an experiment to study the effects of alcohol consumption on sexual stamina, individual participants' drinking histories are an example of

Accepted Answer

Individual participants' drinking histories can introduce variability that affects the outcome of the experiment, making it a confound.

Question 3

Dr. Ayala conducts an experiment where she gives half her participants a yellow pill containing a drug that keeps them awake during psychology lectures. She gives the other half of her participants an identical-looking yellow pill that does not contain the drug. This experimental design controls for

Accepted Answer

This experimental design controls for a placebo effect, as the participants who received the pill without the drug may still experience the effects of the intervention due to the placebo effect. It does not control for experimenter bias, random variables, or confirmation bias.

Question 4

James read a magazine ad about a drug that doctors say may help college students perform better on multiple-choice type tests. Being the inquisitive person that he is, James decided to do an experiment to see if the magazine's claims were true. He administered the drug to one of his classes, and gave the other class a placebo. James then tested the students in both groups on material they had recently discussed in class. In this example, what is the experimental group?

Accepted Answer

The experimental group is the group that receives the treatment or drug being tested, which in this case is the students who received the drug.

Question 5

Dr. Noyd conducted an experiment to determine whether talking to a psychiatrist made depressed people less depressed. He randomly divided participants who scored highly on a depressive inventory into two groups. Group A talked over their problems with a psychiatrist while Group B did nothing. He found that Group A showed significantly more improvement in their depression than did Group B. In Dr. Noyd's experiment, the experimental group refers to

Accepted Answer

The experimental group is the group that receives the treatment, in this case, talking to a psychiatrist.

Question 6

Dr. Dalbey is studying the effects of fatigue on aggression. He hypothesizes that the more fatigue a person is experiencing, the more aggressively the person will behave. Unbeknownst to Dr. Dalbey, the participants' level of hunger also had an impact on their aggression. Hunger could thus be a(n)__________ variable.

Accepted Answer

Hunger is a confounding variable in this study because it is not being controlled for and could be influencing the participants' level of aggression, potentially making it difficult to attribute any observed effects solely to fatigue.

Question 7

A participant in an experiment is told that a particular pill should improve her performance on a cognitive task. The participant is then given the pill, and she performs better than usual on the task. In actuality, the pill did not contain any ingredients that would affect her performance on the task. The participant's improved performance was most likely due to

Accepted Answer

The placebo effect occurs when a participant experiences a perceived improvement in performance or symptoms due to their belief in the efficacy of a treatment, even though the treatment has no therapeutic effect.

Question 8

In Dr. Turgrove's experiment, he includes a control group that receives a placebo. This type of research design is meant to control which confound?

Accepted Answer

A placebo is used to control for participants' expectations, ensuring that any effects observed are due to the independent variable and not the participants' belief in the treatment.

Question 9

Dr. Hood is conducting a research study in which she is examining two different methods for helping to combat social phobia in adolescents. The intervention methods being studied represent the __________ variable.

Accepted Answer

The intervention methods being studied are the independent variable because they are the conditions that Dr. Hood is manipulating to observe their effect on social phobia in adolescents.

Question 10

Dr. Fontenot is studying the effects of fatigue on aggression. He hypothesizes that the more fatigue a person is experiencing, the more aggressively the person will behave. The level of aggression in Dr. Fontenot's study is the __________ variable.

Accepted Answer

The level of aggression in Dr. Fontenot's study is the outcome variable that is dependent on the level of fatigue. Therefore, it is the dependent variable.

Question 11

Tai is interested in how alcohol consumption affects driving ability. He gives college students two, four, or six beers and then measures how many obstacles the students "hit" when they are in a driving simulator. The dependent variable is

Accepted Answer

The dependent variable is the outcome being measured, which in this case is the number of obstacles hit in the driving simulator.

Question 12

In order to minimize the impact of factors other than the independent variable that can cause a change in the depend variable, participants in an experiment should be assigned to either the experimental or control group

Accepted Answer

Random assignment helps to ensure that the two groups are equivalent in all other respects, so that any difference in the dependent variable can be attributed to the independent variable.

Question 13

Laura conducted a study to determine whether her new "puppet" therapy works better than the traditional "talking" therapy. After randomly assigning her own patients to either the "puppet" or "talking" group, Laura herself administered the therapy. This study is most obviously flawed due to the potential for

Accepted Answer

The study is flawed due to experimenter bias, as Laura, who has a vested interest in the outcome, administered the therapy herself, potentially influencing the results.

Question 14

Dr. Kurtz believes that students who use calculators learn the basics of math better. He designs an experiment in which Group A is taught a math concept and allowed to use calculators. Group B is taught the same math concept but is not allowed to use calculators. Then he gives both groups a standardized math test to assess their knowledge of the concept and compares their scores. In Dr. Kurtz's experiment, the standardized math test score is the

Accepted Answer

The standardized math test score is the result being measured and assessed in this experiment, making it the dependent variable. The independent variable is the use of calculators, which is being manipulated to see how it affects the dependent variable. A confound is an extraneous variable that may affect the results of the experiment, and a placebo is a substance or treatment that has no real effect but may be given to control groups in an experiment. Neither of these options is applicable in this scenario.

Question 15

Briana is studying the impact of room temperature on the speed at which students take a 50-question multiple choice exam. In this study, her participants' previous preferences for different temperature rooms is

Accepted Answer

A confound is an extraneous variable that can affect the results of an experiment. In this case, participants' previous preferences for different temperature rooms could influence their performance on the exam, thus confounding the results.

Question 16

Dr. Jiminez investigated the influence of snacking on the onset of sleep in preschool children. One group of preschoolers ate a candy bar prior to bedtime, and the other group ate nothing. Time until the onset of sleep was recorded for each child. In this experiment, eating or not eating the snack is the __________ variable, and the time until the onset of sleep is the __________ variable.

Accepted Answer

Eating or not eating the snack is the independent variable because it is the variable that is being manipulated by the experimenter. The time until the onset of sleep is the dependent variable because it is the variable that is being measured and is expected to change as a result of the manipulation of the independent variable.

Question 17

Sima believes that wearing black clothing causes people to behave more aggressively. In her experiment, she randomly assigns people into two groups. In Group A, participants are given black shirts to wear, while participants in Group B are given white shirts to wear. Each participant is then asked to play a violent video game for fifteen minutes and his or her score is computed. In this experiment, each participant's video game score is the __________ variable.

Accepted Answer

The video game score is the outcome being measured and is therefore the dependent variable. The independent variable is the type of shirt (black or white) that participants are randomly assigned to wear. Random and confounding variables are not applicable in this particular scenario.

Question 18

Which of the following is the most effective way to eliminate experimenter bias?

Accepted Answer

A double-blind design ensures that neither the participants nor the experimenters know who is receiving a particular treatment, thus minimizing experimenter bias.

Question 19

Dr. Kilgore is studying the effects of Prozac on depression. Dr. Kilgore ran a double-blind study on a group of sixty college students. Thirty students received Prozac and thirty students received a placebo. At the beginning and end of the study, Dr. Kilgore administered the Beck Depression Inventory (BDI)to determine the efficacy of the drugs. In this experiment, the group that received Prozac is considered the __________ group.

Accepted Answer

The group that received Prozac is considered the experimental group because they are the ones receiving the treatment being tested.

Question 20

A researcher shows a violent film to one group of participants and a nonviolent film to another before giving both groups a test measuring aggressiveness. Which of the following statements is true?

Accepted Answer

The type of film shown (violent or nonviolent) is the independent variable because it is the variable that is manipulated by the researcher to observe its effect on the dependent variable, which is the level of aggressiveness.

Quiz 1: Introduction to the Science of Psychology