Question 1

Use the following to answer the questions below:
A group of researchers investigated the effect of media usage (whether or not subjects watch television or use the Internet) in the bedroom on "Tiredness" during the day (measured on a 50 point scale).
-Suppose that the researchers found that the individuals who use media in the bedroom tended to be more tired during the day than those who do not. Would it be appropriate for the researchers to conclude that using media in the bedroom causes tiredness during the day?

Accepted Answer

A) True 
 B)False  False

Question 2

Use the following to answer the questions below:
The Admissions Office at a small university has developed a new 10-minute video about the university to send to prospective students. Before mass-producing the DVD, they would like to test whether it is more effective than the current video. Suppose that you have 12 high school student volunteers who have agreed to take part in an experiment. The explanatory variable to be studied is the type of video, with two levels OLD and NEW.
-What specific question would you ask the students to measure as the response variable in this study?

Accepted Answer

Answers will vary.
For the randomized comparative study, you might ask something like "Based on the video alone, would you consider attending the university?" or "Based on the video alone, rate the likelihood of your attending the university on a scale from 1 to 10."
For a matched pairs experiment, you might ask something like "Which video makes you more likely to consider the university, 1 or 2?"

Question 3

Use the following to answer the questions below:
Can people text just as quickly with their off hand as they do their dominant hand? Assume that you have 42 volunteers available to participate in your study, and that the response you will measure is the time it takes to type and send a text message.
-Design a randomized comparative experiment to investigate this question. Be specific about how randomization will be used in your experiment.

Accepted Answer

Randomly assign the 42 subjects to one of two groups. One group will be assigned to send a text message with their dominant hand, while the other group will send the same text message with their off-hand. All participants will send the same message. The time it takes to type and send the message will be recorded and compared for the two groups.

Question 4

Use the following to answer the questions below:
A realtor's website provides information on area homes that are for sale. Identify each of the variables as either categorical or quantitative.
-Size: in square feet

Accepted Answer

The answer of Use the following to answer the questions...

Question 5

Use the following to answer the questions below:
Identify whether each of the following scenarios describe a randomized comparative experiment or a matched pairs experiment.
-On their website, the makers of Cold-EEZE lozenges provide links to studies done to demonstrate the effectiveness of their product at shortening the duration of the common cold. One study, published in the Annals of Internal Medicine, is described as a "randomized, double-blind, placebo-controlled"
study. Briefly explain what the phrase "randomized, double-blind, placebo-controlled"
means.

Accepted Answer

The answer of Use the following to answer the questions...

Question 6

Use the following to answer the questions below:
The USStates dataset, used throughout the textbook, contains information on the 50 U.S. states. A small segment from the dataset is displayed in the following table.
 
-What are the cases in this dataset?

Accepted Answer

A)   States
B)   Percent of residents with a college degree
C)   Residents
D)   USStates dataset

Question 7

Use the following to answer the questions below:
A realtor's website provides information on area homes that are for sale. Identify each of the variables as either categorical or quantitative.
-School District: the school district in which the home is located

Accepted Answer

The answer of Use the following to answer the questions...

Question 8

Use the following to answer the questions below:
A tree enthusiast is interested in estimating the typical length of oak tree leaves. He chooses 30 leaves from the oak tree in his backyard.
-Is this a biased sampling strategy?

Accepted Answer

A) True 
 B)False

Question 9

Use the following to answer the questions below:
A university's Admissions staff sends one of four different representatives to work at college fairs. A study was conducted to evaluate the relative effectiveness of the four representatives. For each college fair over the course of the year, the number of inquiries from students, the type of fair (large or small), the representative who worked at that fair, and the percent of inquiries that resulted in applications were recorded. It was found that one of the representatives was far more effective at getting lots of inquiries.
-What are the cases in this study?

Accepted Answer

A)   College fairs
B)   Representatives
C)   The percent of inquiries that resulted in applications
D)   The number of inquiries from students

Question 10

Use the following to answer the questions below:
The Admissions Office at a small university has developed a new 10-minute video about the university to send to prospective students. Before mass-producing the DVD, they would like to test whether it is more effective than the current video. Suppose that you have 12 high school student volunteers who have agreed to take part in an experiment. The explanatory variable to be studied is the type of video, with two levels OLD and NEW.
-What are the cases in your study?

Accepted Answer

A)   High school students
B)   Type of video
C)   OLD and NEW
D)   Instructional materials

Question 11

A sample of college age students shows an interesting association between hair length (in inches) and height (also in inches). On average, shorter students tend to have longer hair. What is a possible confounding variable that would help explain this relationship?

Accepted Answer

A)   Gender
B)   Age
C)   Grade point average
D)   Local fashion preferences

Question 12

Sampling from a Population
-A population is a subset of the sample.

Accepted Answer

A) True 
 B)False

Question 13

Use the following to answer the questions below:
A group of researchers investigated the effect of media usage (whether or not subjects watch television or use the Internet) in the bedroom on "Tiredness" during the day (measured on a 50 point scale).
-Association implies causation.

Accepted Answer

A) True 
 B)False

Question 14

Use the following to answer the questions below:
State whether the data are best described as a population or a sample.
-The makers of M&M's state that when they package their candies they thoroughly mix the colored candies together and randomly put them into packages. A student purchases a bag of Milk Chocolate M&M's from the vending machine.

Accepted Answer

A)   Sample
B)   Population

Question 15

Use the following to answer the questions below:
A recent study investigated the impact of psychological stress on men's judgments of female body size. The men were randomly assigned to one of two groups; one group was assigned to participate in a stressful task while the other group did not take part in the task. Then the men were asked to rate the attractiveness of female bodies varying in size from emaciated to obese.
-Is a control group used in this experiment?

Accepted Answer

A) True 
 B)False

Question 16

Use the following to answer the questions below:
A high school senior is collecting data on the colleges in which she is interested, including the following variables: Type of college, Tuition, State, Enrollment, Student-Faculty Ratio, Graduation Rate
-Refer to the variables collected by the high school senior looking at colleges. Identify a question that we might ask about relationships between any two (or more) of these variables.

Accepted Answer

The answer of Use the following to answer the questions...

Question 17

Use the following to answer the questions below:
A high school senior is collecting data on the colleges in which she is interested. Identify the variables as either categorical or quantitative.
-Student-Faculty Ratio: the number of students divided by the number of faculty

Accepted Answer

The answer of Use the following to answer the questions...

Question 18

In each situation, indicate whether the method of data collection is biased.
-A reporter from the campus newspaper is writing an article about student opinions on Greek organizations (sororities and fraternities). For his article, he visits all of the Greek houses on campus and interviews a random sample of residents of each house.

Accepted Answer

A)   Biased
B)   Not biased

Question 19

Use the following to answer the questions below:
A realtor's website provides information on area homes that are for sale, including the following variables: List Price, School District, Size, Style.
-Refer to the variables provided by the realtor. Identify a question that we might ask about relationships between any two (or more) of these variables.

Accepted Answer

The answer of Use the following to answer the questions...

Question 20

Use the following to answer the questions below:
The USStates dataset, used throughout the textbook, contains information on the 50 U.S. states. A small segment from the dataset is displayed in the following table.
 
-Data from the state of Connecticut were used to determine that 42.7% of state residents had a college degree. What were the cases from Connecticut used to arrive at this figure?

Accepted Answer

A)   Residents of Connecticut
B)   The state of Connecticut
C)   42.7 percent of the Connecticut residents with a college degree
D)   The residents of California, Colorado, and Connecticut

Exam 1: Collecting Data

Use the following to answer the questions below: A realtor's website provides information on area homes that are for sale. Identify each of the variables as either categorical or quantitative. -Size: in square feet

Use the following to answer the questions below: The USStates dataset, used throughout the textbook, contains information on the 50 U.S. states. A small segment from the dataset is displayed in the following table. -What are the cases in this dataset?

Use the following to answer the questions below: A realtor's website provides information on area homes that are for sale. Identify each of the variables as either categorical or quantitative. -School District: the school district in which the home is located

Use the following to answer the questions below: A tree enthusiast is interested in estimating the typical length of oak tree leaves. He chooses 30 leaves from the oak tree in his backyard. -Is this a biased sampling strategy?

A sample of college age students shows an interesting association between hair length (in inches) and height (also in inches) . On average, shorter students tend to have longer hair. What is a possible confounding variable that would help explain this relationship?

Sampling from a Population -A population is a subset of the sample.

Use the following to answer the questions below: A group of researchers investigated the effect of media usage (whether or not subjects watch television or use the Internet) in the bedroom on "Tiredness" during the day (measured on a 50 point scale). -Association implies causation.

Use the following to answer the questions below: A high school senior is collecting data on the colleges in which she is interested. Identify the variables as either categorical or quantitative. -Student-Faculty Ratio: the number of students divided by the number of faculty