Question Bank in line with Managerial Statistics, Abbreviated Edition, International Edition,Keller,8e

CHAPTER 1 SECTION 1: WHAT IS STATISTICS?




MULTIPLE CHOICE



1. You take a random sample of 100 students at your university and find that their average
GPA is 3.1. If you use this information to help you estimate the average GPA for all students
at your university, then you are doing what branch of statistics?

a. Descriptive statistics

b. Inferential statistics

c. Sample statistics

d. Population statistics



ANS: B PTS: 1 REF: SECTION 1.1



2. A company has developed a new computer sound card whose average lifetime is unknown.
In order to estimate this average, 200 sound cards are randomly selected from a large
production line and tested; their average lifetime is found to be 5 years. The 200 sound
cards represent a:

a. parameter.

b. statistic.

c. sample.

d. population.



ANS: C PTS: 1 REF: SECTION 1.1



3. A company has developed a new computer sound card whose average lifetime is unknown.
In order to estimate this average, 200 sound cards are randomly selected from a large
production line and tested; their average lifetime is found to be 5 years. The 5 years
represents a:

, a. parameter.

b. statistic.

c. sample.

d. population.



ANS: B PTS: 1 REF: SECTION 1.1



4. A descriptive measure that is computed from a sample is called a:

a. parameter.

b. statistic.

c. population.

d. sample.



ANS: B PTS: 1 REF: SECTION 1.1



5. A summary measure that is computed from a population is called a:

a. sample.

b. statistic.

c. population.

d. parameter.



ANS: D PTS: 1 REF: SECTION 1.1

,6. Which of the following is a measure of the reliability of a statistical inference?

a. A population parameter.

b. A significance level.

c. A descriptive statistic.

d. A sample statistic.



ANS: B PTS: 1 REF: SECTION 1.1



7. A politician who is running for the office of governor of a state with 4 million registered
voters commissions a survey. In the survey, 54% of the 5,000 registered voters interviewed
say they plan to vote for her. The population of interest is:

a. the 4 million registered voters in the state.

b. the 5,000 registered voters interviewed.

c. the 54% who plan to vote for her.

d. all the residents of the state.



ANS: A PTS: 1 REF: SECTION 1.1



8. A company has developed a new battery and wants to estimate its average lifetime. A
random sample of 500 batteries is tested and the average lifetime of this sample is found to
be 225 hours. The 225 hours is the value of a:

a. parameter.

b. statistic.

c. sample.

d. population.



ANS: B PTS: 1 REF: SECTION 1.1

, 9. The process of using sample statistics to draw conclusions about population parameters is
called:

a. finding the significance level.

b. calculating descriptive statistics.

c. doing inferential statistics.

d. calculating the confidence level.



ANS: C PTS: 1 REF: SECTION 1.1



10. Which of the following represents a population, as opposed to a sample?

a. 1,000 respondents to a magazine survey which has 500,000 subscribers.

b. The first 10 students in your class completing a final exam.

c. Every fifth student to arrive at the book store on your campus.

d. All registered voters in the State of Michigan.



ANS: D PTS: 1 REF: SECTION 1.1



11. A researcher at Michigan State University (MSU) wants to estimate the average number of
credits earned by students last semester at MSU. She randomly selects 500 students from
last semester and finds that they averaged 14.85 credits per student. The population of
interest to the researcher is:

a. all MSU students.

b. all college students.

c. all MSU students enrolled last semester.

d. the 500 MSU students selected at random.



ANS: C PTS: 1 REF: SECTION 1.1