Exam 8: Experimental Design

Elena randomly asks students of a class to taste either Coke or Pepsi. Students rate their liking for the soda they taste on a scale of 1 to 10. This is an example of a _____ design.

When individuals participate in only one condition, it is a(n) _____ design. When individuals participate in all conditions, it is a _____ design.

When a confounding variable is present in an experiment, _____.

To achieve internal validity, a researcher must design and conduct experiments where only the _____ variable can be the cause of the results.

Which of the following is a drawback of the matched pairs design?

In order to observe the influence of environmental factors on alcohol consumption, Leila asks participants to come to her laboratory, fill out a questionnaire, and consume alcohol. She finds that over time, fewer and fewer participants show up to take part in the experiment. This decrease in the number of participants in the experiment is called _____.

A matched pairs design is most likely to be used when:

A psychologist is interested to know which of two sorting techniques leads to better memory performance in 6-year-olds. Each participant first sorts a set of pictures any way he or she likes. Recall is then tested. After this, each participant is required to sort an equivalent set of pictures into five predetermined categories. Recall for the items in this step is then tested. What procedure does this study represent?

Which of the following is an advantage of using a pretest-posttest design over using a posttest-only design?

If the two groups involved in an experiment are not equivalent, _____.

To study the effect of the type of stimulus on memory recall, Zhong subjects participants to either an auditory or visual presentation of a poem. After the presentation, the participants are asked to answer several questions about the poem. Which type of experimental design has Zhong employed?

Irene wants to examine the effect of a defendant's appearance on the judgment of guilt for a crime. She has participants read an identical account of the crime except for the defendant's appearance. A group of high school students receive the description of an attractive defendant, while a group of senior citizens receive the description of an unattractive defendant. Both groups are then asked to rate the defendant's guilt on a seven-point scale. A major cause for confusion in Madison's experiment is the _____.

In a Solomon four-group design, if there is no impact of the pretest, _____.

In a _____ design, half the participants receive only a posttest, while the other half receives both a pretest and a posttest.

Ahmed conducts a study to test the effectiveness of a drug. He surveys the clients twice-once at intake and then six months later. He finds that the drug was overall effective, but approximately 55 percent of the original sample stopped using the drug. Therefore, he does not have posttest data for them. In this case, what is likely to be an alternative explanation for the results obtained by Ahmed?

Which of the following accurately describes a disadvantage of using a pretest-posttest design?

An experiment can be assumed to have internal validity if:

Jose states that he has counterbalanced the conditions in his experiment. What does this mean?

Aisha wants to examine the effect of room temperature on task performance. She places one group of participants in a room that is set to a temperature of 54 degrees, a second group in a room that is set to a temperature of 72 degrees, and a third group in a room that is set to a temperature of 90 degrees. She then measures the amount of time it takes each group to complete the same task. This design would best represent a(n) _____ design.

Wendy wants to know if a new sports drink improves physical performance. The number of push-ups each participant can complete in one minute is recorded first. The participants are then given eight ounces of the sports drink, and the number of push-ups completed in one minute is recorded again. Wendy finds that the number of push-ups completed is less after consuming the new sports drink. This finding is likely the result of a _____ effect.