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Concept explainers
For each of the following pairs of variables, is there likely to be a positive association, a negative association, or no association? Briefly explain your reasoning.
- Amount of alcohol consumed and performance on a test of coordination, where a high score represents better coordination.
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(a)
To explain whether the relationship between amount of alcohol and performance on test is negative or positive or no relationship at all.
Answer to Problem 3.1E
Negative relationship.
Explanation of Solution
The relationship between amount of alcohol and performance on test is negative because if a person consumes the alcohol his/her performance will definitely go down on the test. Which means increase in consumption of alcohol implies decrease in the performance on test. Therefore, there is negative association.
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(b)
To explain whether the relationship between Height and Grade point average is negative or positive or no relationship at all.
Answer to Problem 3.1E
No association
Explanation of Solution
There is no relationship between the height and grade point average because height has no effect on Grade points. Which implies no association between these variables.
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(c)
To explain whether the relationship between Weight of the car and average no. of miles is negative or positive or no relationship at all.
Answer to Problem 3.1E
Negative relationship
Explanation of Solution
There is negative relationship between Weight of the car and average no. of miles because weight decreases the average no. miles driven by a car. As the weight increases the average number of miles decrease. Therefore, there is negative relationship between these variables.
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Chapter 3 Solutions
Mind on Statistics
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