Topic: The Scientific Approach
ANS: a, Remember the Facts, LO 1.7 Explain how researchers use the correlational technique to study relationships between two or more variables., (1)
% correct 76 a= 76 b= 2 c= 3 d= 16 r = .39
APA=2.4
TB_01_126_The Scientific Approach_Apply_LO 1.7, APA 2.4
A correlation coefficient shows that smoking and life expectancy are indeed related. As a result, a researcher could predict that ________ if the direction of the relationship is known.
if a person smokes a lot of cigarettes, he or she will have less money monthly to buy gas
the person’s life expectancy will go up or down based on the number of cigarettes the person smokes daily
Correct. The directionality of the correlation coefficient can predict this relationship.
if a person smokes cigarettes, he or she will eventually develop lung cancer
a person’s lungs will repair themselves and he or she will live a longer life
Incorrect. The correlation mentioned did not include information about lungs.
Topic: The Scientific Approach
ANS: b, Apply What You Know, LO 1.7 Explain how researchers use the correlational technique to study relationships between two or more variables., (3)
APA=2.4
TB_01_127_The Scientific Approach_Remember_LO 1.7, APA 2.4
Which of the following correlation coefficients represents the strongest relationship between two variables?
a) .50
Incorrect. Because –.75 is closer to +1.00, it is the strongest relationship of the options.
b) .25
c) –.25
d) –.75
Correct. The closer a correlation coefficient is to +1.00, the stronger the relationship it indicates.
Topic: The Scientific Approach
ANS: d, Remember the Facts, LO 1.7 Explain how researchers use the correlational technique to study relationships between two or more variables., (3)
APA=2.4
TB_01_128_The Scientific Approach_Apply_LO 1.7, APA 2.4
Which correlation coefficient is most likely to describe the relationship between brushing one’s teeth and the number of cavities one gets?
a) –.62
Correct. One would expect that as brushing increases, cavities tend to decrease. Thus, a negative correlation would best describe the relationship. Further, one would expect the relationship to be fairly strong and thus closer to +1.0 than to 0.
b) .83
Incorrect. This correlation coefficient would suggest that as brushing increases, the number of cavities increases. We would hope that the relationship between tooth brushing and the number of cavities one gets would be a strong negative correlation.
c) –.08
d) .45
Topic: The Scientific Approach
ANS: a, Apply What You Know, LO 1.7 Explain how researchers use the correlational technique to study relationships between two or more variables., (2)
APA=2.4
TB_01_129_The Scientific Approach_Apply_LO 1.7, APA 2.4
Drinking orange juice is negatively correlated with the risk of cancer. Based on this information, which of the following statements is true?
a) The more orange juice you drink, the higher your risk of cancer.
Incorrect. When the two variables move up or down together—that is a positive correlation.
b) The more orange juice you drink, the lower your risk of cancer.
Correct. When as one variable goes up (juice drinking), the other goes down (risk of cancer); that is a negative correlation.
c) The less orange juice you drink, the lower your risk of cancer.
d) Drinking orange juice causes people to be cancer free.
Topic: The Scientific Approach
ANS: b, Apply What You Know, LO 1.7 Explain how researchers use the correlational technique to study relationships between two or more variables., (1)
APA=2.4
TB_01_130_The Scientific Approach_Remember_LO 1.7, APA 2.4
A correlation coefficient represents two things: ________ and ________.
a) a representative sample; strength
b) strength; direction of the relationship
Correct. These are the two concepts that a correlation coefficient represents.
c) the experimental group; control group