Concept explainers
(a)
To identify the explanatory and response variables in this experiment.
(a)
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Answer to Problem T4.14SPT
Explanatory variable: The treatment given (caffeine capsule or placebo).
Response variable: The time it takes to complete the tapping task.
Explanation of Solution
In an experimental study, the explanatory variable is the variable that is manipulated by the researcher. Explanatory Variable is also known as the independent or predictor variable, it explains variations in the response variable.
Thus, in this case,
Explanatory variable: The treatment given (caffeine capsule or placebo)
And the Response variable: The time it takes to complete the tapping task.
(b)
To explain how was blocking used in the design of the experiment and what was the benefit of blocking in the experiment.
(b)
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Explanation of Solution
Blocking was used in this experiment as each of the
(c)
To explain what problem does confounding caused.
(c)
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Explanation of Solution
The problem confounding caused is that after the first trial, subjects might practice the tapping task and do better the second time, If all the subjects got caffeine the second time, the researches would not know if the increase was due to the practice or the caffeine.
(d)
To explain could this experiment have been carried out in a double-blind manner or not.
(d)
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Answer to Problem T4.14SPT
Yes it could be.
Explanation of Solution
Yes,this experiment could have been carried out in a double-blind manner if neither the subjects nor the people who come in contact with them during the experiment (including those who record the number of taps) have knowledge of the order in which the caffeine or placebo was administered.
Chapter 4 Solutions
PRACTICE OF STATISTICS F/AP EXAM
Additional Math Textbook Solutions
Basic Business Statistics, Student Value Edition
Elementary Statistics (13th Edition)
A First Course in Probability (10th Edition)
Calculus: Early Transcendentals (2nd Edition)
College Algebra (7th Edition)
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