Chapter 6 Review Statistics Experimental Design

A market research company wishes to find out whether the population of students at a university prefers Starbucks or Dunkin Donuts. A random sample of students is selected, and each student is asked first to try both but the order they try them is randomly decided with a coin toss (heads: Starbucks, then Dunkin. tails: vice versa). They then indicate which brand they prefer. This is an example of

• completely randomized experiment

• an observational study

• a blocked experiment

• matched pairs experiment

In order to perform an experiment using 60 members of a gym, I first divide the list of members into men and women because I feel that the results will be different based on gender. I then randomly choose 30 men and 30 women. I assign half of the men to the treatment group and half to the control group. I repeat this procedure with the women. This is an example of a:

• completely randomized experiment

• blocked experiment

• matched pairs experiment

• observational study

Steve wanted to see if different types of fertilizer influence sunflower growth. What is the explanatory variable?

• type of fertilizer

• sunflower grown without fertilizer

A student is planning an experiment to find out how the height from which he drops a ball affects how high the ball bounces. The response variable is the _____.

• Diameter of the ball

• Force acting on the ball

• Height that the ball bounces

• Height from which the ball is dropped

To investigate whether standing up while studying affects performance in an algebra class, a teacher assigns half of the 30 students in his class to stand up while studying and assigns the other half to not stand up while studying. Which of the following best describes this plan?

• This is an observational study

• This is an experiment

• This is a stratified random sample

• This is a cluster sample

An ​ (a)   does not have treatments imposed.

An ​ (b)   has treatments imposed.

• Observational Study

• Experiment

Match the following

• Double-Blind Study

• A special case of a randomized block design. Using a blocking variable, subjects (whether they are people or not) are arranged in pairs matched on relevant factors.

• Matched Pairs Design

• Subjects do not know which treatment they are receiving, but members of the research team do, or vice versa.

• Single-Blind Study

• Treatments are assigned completely at random within each block.

• Randomized Complete Block Design

• Neither the subjects nor the members of the research team who interact with them know which

  treatment a subject is receiving.

• Completely Randomized Design

• Treatments are assigned to experimental units

  completely at random.

Four groups of randomly selected people are assigned a different diet. After six months, the blood pressures of each group are compared.

• Observational Study

• Experiment

In a survey of a sample of high school students, 43% said that their mother has taught them the most about managing money.

• parameter

• statistic

A poll is taken from 100 seniors in a high school where the senior class has 575 students. This is an example of a ______________.

• Sample

• Population