Data: Description, Collection, And Sampling

Student ID: 21458913

Exam: 250711RR - Data: Description, Collection, and Sampling

When you have completed your exam and reviewed your answers, click Submit Exam. Answers will not be recorded until you hit Submit Exam. If you need to exit before completing the exam, click Cancel Exam.

Questions 1 to 20: Select the best answer to each question. Note that a question and its answers may be split across a page break, so be sure that you have seen the entire question and all the answers before choosing an answer.

1. What is the difference between a histogram and a bar chart? A. A histogram and a bar chart both reflect qualitative data.

B. The adjacent rectangles in a bar chart have a gap, while those for a histogram don't.

C. The adjacent rectangles in a histogram have a gap, while those for a bar chart don't.

D. A histogram reflects qualitative data, while the bar chart represents quantitative data.

2. To answer the question, refer to the following data.

Ten students were sampled at random from a student population. Each was asked how many courses he or she was planning on studying in the upcoming year. The following is a list of the reported data values: 1, 2, 2, 3, 4, 5, 5, 5, 5, 6

What is the standard deviation for the data values? A. 2.84

B. 1.44

C. 1.687

D. 2.56

3. When creating a histogram, it's important to ensure that the classes of data satisfy which properties? A. They must be mutually exclusive and exhaustive.

B. No requirements are made; the individual creating the graph is free to choose any classes.

C. They must be all the same size.

D. They must include each interval on the number line.

4. In a sample with mean x = 12 and standard deviation s = 3.5, a data point at 16.8 would have what sample z-score? A. 1.4

B. 4.8

C. We can't know the answer without knowing the population mean μ and standard deviation σ. D. 1.37

5. If there are an odd number of data values in a set, the median will be the A. average of the two end values.

B. value that appears in the center.

C. value that appears the greatest number of times.

D. average of all of the values divided by the number of values in the set.

6. To answer the question, refer to the following list of raw data.

63, 71, 72, 77, 77, 78, 86, 77, 88, 88

What is the median for the data? A. 77.5

B. 77

C. 88

D. 77.7

7. Use the following data sample to answer the question.

4, 14, 6, 9, 21, 3, 7, 10

What is the mean of this data sample? A. There's no mean value.

B. 7

C. 8

D. 9.25

8. Which of the following statements about interpreting standard deviation is true? A. The Empirical Rule can't be applied unless the frequency distribution is mound-shaped and symmetric. Chebyshev's Rule can be applied to any data set, regardless of the shape of its frequency distribution.

B. Neither the Empirical Rule nor Chebyshev's Rule can be applied to data unless the frequency distribution is mound-shaped and symmetrical.

C. Chebyshev's Rule can't be applied unless the frequency distribution is mound-shaped and symmetric. The Empirical Rule can be applied to any data set, regardless of the shape of its frequency distribution.

D. Neither Chebyshev's Rule nor the Emprical Rule require any assumptions about the frequency distribution.

9. Which of the following statements is true about a stem-and-leaf plot? A. It uses vertical bars to illustrate a probability distribution.

B. It separates data at the decimal point, creating horizontal rows whose values are close together.

C. Stem-and-leaf plots are histograms whose bars have been arranged in decreasing order of frequency.

D. It involves creating columns of dots, one for each datum in the sample.

10. If a great many data values cluster to the left of a data distribution, which then tails off to the right, the distribution is referred to as A. leftward skewed.

B. rightward skewed.

C. uniform.

D. normal.

11. Use the following data sample to answer the question.

4, 14, 6, 9, 21, 3, 7, 10

What is the median of this data sample? A. 9.25

B. 8

C. 7

D. There's no median value.

12. When obtaining data by _______ it's most important to inquire about the purposes of the original experimenter. A. collecting data observationally

B. performing a designed experiment

C. reading a published source

D. conducting a survey

13. To answer the question, refer to the following list of raw data.

63, 71, 72, 77, 77, 78, 86, 77, 88, 88

What is the mode for the data? A. 88

B. 77

C. 77.5

D. 77.7

14. Given the data set 3, 6, 2, 9, –1, 0, compute ∑(x + 1)2. A. 25

B. 625

C. 137

D. 175

15. To answer the question, refer to the following list of raw data.

63, 71, 72, 77, 77, 78, 86, 77, 88, 88

What is the mean for the data? A. 77.7

B. 77

C. 77.5

D. 88

16. Which of the following statements is true?

End of exam

A. In a true census, no inferential statistics can be done, because the entire population is the sample.

B. A population is the object upon which we collect data.

C. When taking a sample from the population, the variable involved will always be qualitative.

D. The definition of a census is the decennial census of the United States of America.

17. Which of the following involves inferential statistics as opposed to descriptive statistics? A. The city business office reported 35 building permits for new single-family housing units.

B. A class of 50 statistics students earned an average grade of 73.5.

C. A local cable system, using a sample of 500 subscribers, estimates that 40 percent of its subscribers watch a premium channel at least once per day.

D. The Alcohol, Tobacco and Firearms department reported that Houston had 1,791 registered gun dealers in 1997.

18. Which of the following are parameters of a population? A. α and σ  B. μ and σ  C. μ and x D. σ and n

19. To answer the question, refer to the following data.

Ten students were sampled at random from a student population. Each was asked how many courses he or she was planning on studying in the upcoming year. The following is a list of the reported data values: 1, 2, 2, 3, 4, 5, 5, 5, 5, 6

What is the variance for the data values? A. 2.56

B. 2.844

C. 1.6

D. 1.687

20. Use the following data sample to answer the question.

4, 14, 6, 9, 21, 3, 7, 10

What is the range of this data sample? A. 18

B. 6

C. 10

D. 4