You passed this Milestone
24 questions were answered correctly.
3 questions were answered incorrectly.
2 questions were skipped. These were marked incorrect.
1
A trainer is studying the effects of vitamin D on his a
...
You passed this Milestone
24 questions were answered correctly.
3 questions were answered incorrectly.
2 questions were skipped. These were marked incorrect.
1
A trainer is studying the effects of vitamin D on his athletes. He has realized that there are many potential
confounding factors, such as gender and age. To limit the effect of these confounding variables, he decided to
first group two athletes together based on these variables (for example, two 21-year-old males). Then he
randomly assigned one person to receive the vitamin D and the other to receive a sugar pill.
What type of experimental design does this situation demonstrate?
Completely Randomized Design
Randomized Block Design
Matched-Pair Design
Simple Random Design
RATIONALE
By matching on age and gender this is called a matched-pair design.
CONCEPT
Matched-Pair Design
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2
A team of researchers want to measure the distance covered while driving compared to a car's driving speed.
Which statement is correct?
The speed of the car is a dependent variable.
The speed of the car is a confounding variable.
The speed of the car is an explanatory variable.
The speed of the car is a response variable.
RATIONALE
The outcome is the response, dependent or y -variable. The variable that explains the response is the
explanatory, independent or x-variable. In this case the explanatory variable is speed with distance being the
response.
CONCEPT
Variables
3
Melissa is conducting a survey of her classmates because her teacher wants the class to learn more about hygiene
habits. Melissa has developed a list of 10 questions. “Do you brush your teeth every day?” is the first question
she asks.
Which type of question is Melissa asking?
Open and binomial question
Open question
Closed and binomial question
Closed question
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RATIONALE
In this question, the responses are limited and there are only 2 responses. This would be a closed binomial
question type.
CONCEPT
Question Types
4
A survey result shows that cell phone usage among teenagers rose from 63% in 2006 to 71% in 2008.
Of the following choices, which statement about cell phone use among teenagers is true?
Cell phone usage rose by 12.7%.
Cell phone usage rose by 8%.
Cell phone usage rose by 12.7 perce
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