a) it is a procedure for assigning people to experimental and control groups
b) it is a procedure in which each subject has the same possibility of being assigned to a given group
c) it is a procedure in which subjects are assigned to a positive correlation or a negative correlation condition
Correct. Subjects can never be assigned to a type of correlation.
d) it is a procedure that allows individual characteristics to be roughly balanced between groups
Incorrect. Random assignment does allow individual characteristics to be roughly balanced between groups.
Topic: The Scientific Approach
ANS: c, Remember the Facts, LO 1.8 Identify the steps involved in designing an experiment., (2)
% correct 63 a= 11 b= 7 c= 63 d= 19 r = .19
APA=2.4
TB_01_154_The Scientific Approach_Remember_LO 1.8, APA 2.4
Which of the following is CORRECT concerning random assignment?
a) In random assignment, each participant has an equal chance for each condition.
Correct. In random assignment each participant has an equal chance of being assigned.
b) In random assignment, each participant is assigned alphabetically to each condition.
c) Random assignment can only be determined after an experiment is over.
d) The best formula for random assignment is birth dates.
Incorrect. Birth dates are not random because many people are born on the same day.
Topic: The Scientific Approach
ANS: a, Remember the Facts, LO 1.8 Identify the steps involved in designing an experiment., (1)
% correct 90 a= 90 b= 2 c= 4 d= 4 r = .20
% correct 90 a= 90 b= 3 c= 3 d= 3 r = .26
APA=2.4
Experimental Hazards and Controlling for Effects
Learning Objective 1.9 - Recall two common sources of problems in an experiment and some ways to control for these effects.
TB_01_155_The Scientific Approach_Apply_LO 1.9, APA 2.4
Which of the following situations best illustrates the placebo effect?
a) You sleep because you are tired.
b) You throw up after eating bad meat.
Incorrect. Throwing up after eating bad food is caused by a physiological reflex, not by expectations, as would be the case in a placebo effect.
c) You have surgery to repair a defective heart valve.
d) You drink a nonalcoholic drink and become “intoxicated” because you think it contains alcohol.
Correct. The placebo effect is brought on by expectations, and in this case you felt drunk only because you believed you were drinking alcohol.
Topic: The Scientific Approach
ANS: d, Apply What You Know, LO 1.9 Recall two common sources of problems in an experiment, and some ways to control for these effects., (1)
% correct 94 a= 5 b= 1 c= 0 d= 94 r = .32
% correct 98 a= 1 b= 0 c= 1 d= 98 r = .22
APA=2.4
TB_01_156_The Scientific Approach_Remember_LO 1.9, APA 2.4
The placebo effect means ________.
a) all conditions in an experiment are the same
b) that there is no control group
Incorrect. The placebo effect is one reason why it’s necessary to have a control group.
c) the expectations of the participants influence their behavior
Correct. The placebo effect occurs when the expectations of the participants influence their behavior.
d) experimenter bias causes the subjects to act strangely
Topic: The Scientific Approach
ANS: c, Remember the Facts, LO 1.9 Recall two common sources of problems in an experiment, and some ways to control for these effects., (2)
% correct 77 a= 11 b= 8 c= 77 d= 4 r = .44
APA=2.4
TB_01_157_The Scientific Approach_Apply_LO 1.9, APA 2.4
Angela was participating in an experiment in which she was given a pill that was supposed to cause her to get drowsy. Five minutes after taking the pill, Angela reported that she felt drowsy and wanted to lie down. The pill was actually made of sugar and had no ingredients to cause drowsiness. How do you explain Angela’s drowsy feeling?