8. The Tennessean, an online newspaper located in Nashville, Tennessee, conducts a
daily poll to obtain reader opinions on a variety of current issues. In a recent poll, 762
readers responded to the following question: “If a constitutional amendment to ban a
state income tax is placed on the ballot in Tennessee, would you want it to pass?”
Possible responses were Yes, No, or Not Sure (The Tennessean website, February 15,
2013).
a. What was the sample size for this poll?
The sample size is 762.
b. Are the data categorical or quantitative?
The data is Categorical.
13. Figure 1.7 provides a bar chart showing the annual revenue for Google from 2004 to
2014. (The Wall Street Journal, August 19, 2014).
a. What is the variable of interest?
Google revenue in billions of dollars.
b. Are the data categorical or quantitative?
Quantitative
c. Are the data time series or cross-sectional?
Time series
d. Comment on the trend in Google revenue over time.
The revenue of Google underwent a gradual increase overtime.
24. A sample of midterm grades for five students showed the following results: 72, 65,
82, 90, 76. Which of the following statements are correct, and which should be
challenged as being too generalized?
a. The average midterm grade for the sample of five students is 77.
(72 + 65 + 82 + 90 + 76)/5 = 77 → Correct
b. The average midterm grade for all students who took the exam is 77.
This statement is too generalized as 77 is just the average grade of the sample of 5
students, but not of the whole population who took the exam.
c. An estimate of the average midterm grade for all students who took the exam is 77.
Correct
d. More than half of the students who take this exam will score between 70 and 85.
This statement is correct for the sample, but doesn’t make sense when it comes to the
entire population.
e. If five other students are included in the sample, their grades will be between 65 and 90.
There’s no statistical clue to guarantee that the other students, who is currently outside the
sample, have the grades between 65 and 90.