Experimental Design (random,blocked,matched pairs)

Runners after an ultramarathon commonly develop respiratory infections. We want to know if taking 600 milligrams of vitamin C daily will reduce these infections. Researchers randomly assigned 100 ultramarathon runners to receive either vitamin C or placebo. All subjects were watched for 14 days after the big race to see if infections developed. The type of design used here?

• matched pairs design

• randomized block design

• completely randomized design

• double-blind observational study

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CCSS.HSS.IC.B.3

In order to perform an experiment using 60 members of a gym, I first divide the list of members into former athletes and members who have never played sports because I feel that the results will be different based on previous experience. I then choose 30 former athletes and 30 non-athletes. I randomly assign half of the athletes to the treatment group and half to the control group. I repeat this procedure with the non-athletes. This is an example of a(n)

• observational study

• randomized block design

• matched pairs design
• double blind simple random sample

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CCSS.HSS.IC.B.3

True or False: An example of a matched pair experimental design is having one twin receive treatment A and the second twin receive treatment B

• True
• False

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CCSS.HSS.IC.B.3

A researcher randomly selected 30 people to participate in a study to investigate which of two materials, A or B, used in the heels of sneakers will last longer. The researcher wants to make sure they take into account the shoe size in the design.

Design: Order the participants by shoe size, largest to smallest. Assign the person with the largest shoe to try material A. Assign the next biggest size shoe to try material B. Continue to alternate who gets which material by size of shoe.

What kind of design is this?

• This is a completely randomized design.

• This is a matched pairs design.

• This is a observational study.

• This is a randomized block design.

• This is a voluntary response survey.

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CCSS.HSS.IC.B.3

What kind of experiment is shown in the picture?

• Randomized Block Design

• Completely Randomized Design

• Matched Pairs

• SRS

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CCSS.HSS.IC.B.3

What kind of experiment is shown in the picture?

• Randomized Block Design

• Completely Randomized Design

• Matched Pairs

• SRS

Tags

CCSS.HSS.IC.B.3

An experiment compares the taste of a new spaghetti sauce with the taste of a successful spaghetti sauce. Each of a number of tasters is given either the new sauce or the successful sauce based on a random number generator. The tasters then rate the sauce on a scale of 1-5. This is called a(n)...

• observational study.
• matched pairs design experiment. 
• completely

  randomized design experiment. 

• block design experiment. 

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CCSS.HSS.IC.B.3

A pottery school wants to study whether the glaze of stoneware bowls is affected by the temperature used to harden the bowls. The study will use 3 different types of clay because glaze can affect different clay in different ways. Eight bowls will be made with each clay type for a total of 24 bowls, and 4 different temperatures will be used. What is the best design to use for the study?

• A completely randomized design. Randomly assign temperatures so that 6 bowls are glazed at each temperature.

• A completely randomized design. Randomly assign temperatures so that 2 bowls of each clay type are glazed at each temperature.

• A randomized block design. Randomly assign temperatures so that 2 bowls of each clay type are glazed at each temperature.

• A matched pairs design. Randomly assign temperatures so that 2 bowls of each clay type are glazed at each temperature.

Tags

CCSS.HSS.IC.B.3