b) the individuals.
c) Dr. Jenkins.
d) the number of minutes individuals run on the treadmill.
Correct. This is the variable that is manipulated by the researcher, so it is the independent variable.
Topic: The Scientific Approach
ANS: d, Apply What You Know, LO 1.8 Identify the steps involved in designing an experiment., (2)
APA=2.4
TB_01_149_The Scientific Approach_Apply_LO 1.8, APA 2.4
Marjorie has individuals cycle on stationary bikes for 0, 10, 20, or 30 minutes, after which she measures their self-reported mood. In this hypothetical study, the dependent variable is:
a) the self-reported mood.
Correct. This is the variable that is measured, so it is the dependent variable.
b) the individuals who do not ride on the stationary bike.
c) the number of minutes individuals ride the bike.
Incorrect. This is the variable that is manipulated, so it is the independent variable.
d) the riding of bikes.
Topic: The Scientific Approach
ANS: a, Apply What You Know, LO 1.8 Identify the steps involved in designing an experiment., (2)
APA=2.4
TB_01_150_The Scientific Approach_Apply_LO 1.8, APA 2.1, 2.4
In a laboratory, smokers are asked to “drive” using a computerized driving simulator equipped with a stick shift and a gas pedal. The object is to maximize the distance covered by driving as fast as possible on a winding road while avoiding rear-end collisions. Some of the participants smoke a real cigarette immediately before climbing into the driver’s seat. Others smoke a fake cigarette without nicotine. You are interested in comparing how many collisions the two groups have. In this study, the participants who smoke a cigarette without nicotine comprise the ________.
a) control group
Correct. A control group gets either no treatment or treatment with no effect; in this case, experimenters are controlling for the possibility that the cigarette itself (not the nicotine) might cause people to get into collisions.
b) driving simulator
c) experimental group
Incorrect. The experimental group does get treatment that is expected to have an effect, whereas the control group gets either no treatment or treatment without effect.
d) no-control group
Topic: The Scientific Approach
ANS: a, Apply What You Know, LO 1.8 Identify the steps involved in designing an experiment., (2)
% correct 78 a= 78 b= 0 c= 2 d= 0 r = .44
APA=2.1; 2.4
TB_01_151_The Scientific Approach_Understand_LO 1.8, APA 2.4
Ideally, everything in the experimental situation except the _________ is held constant.
a) inferential statistics
b) placebos
Incorrect. Placebos do not vary in ways that will affect outcomes.
c) independent variables
Correct. Independent variables are manipulated by the experimenter; thus, they cannot be held constant.
d) hypotheses
Topic: The Scientific Approach
ANS: c, Understand the Concepts, LO 1.8 Identify the steps involved in designing an experiment., (2)
% correct 77 a= 8 b= 9 c= 77 d= 5 r = .34
% correct 74 a= 14 b= 3 c= 74 d= 8 r = .28
APA=2.4
TB_01_152_The Scientific Approach_Understand_LO 1.8, APA 2.4
A good control group ________.
a) contains at least one confound
b) has a limited number of dependent variables
c) has a limited number of research participants
Incorrect. In fact, a good control group would have the same number of participants as an experimental group.
d) holds constant all variables in the experiment
Correct. A control group is used as a baseline of comparison, so all variables should be held as constant as possible to avoid any compound.
Topic: The Scientific Approach
ANS: d, Understand the Concepts, LO 1.8 Identify the steps involved in designing an experiment., (1)
APA=2.4
TB_01_153_The Scientific Approach_Remember_LO 1.8, APA 2.4
All of the following are accurate statements regarding random assignment EXCEPT _________.