SECTION 1.1 EXERCISES

For Exercises 1.1 and 1.2, see page 3; for Exercise 1.3, see page 5; for Exercise 1.4, see page 5; and for Exercises 1.5 and 1.6, see page 6.

Question 1.7

1.7 How do you do online research? A study of 552 first-year college students asked about their favorite choice for doing online research. Possible choices were “Google or Google Scholar,” “Library database or website,” “Wikipedia or online encyclopedia,” and “Other.” Names of the students were not recorded, but the students were numbered from 1 to 552 in the data file. The researchers also recorded age, sex, and major area of study for each student.

  1. (a) What are the cases?

  2. (b) Identify the variables and their possible values.

  3. (c) Classify each variable as categorical or quantitative. Be sure to include at least one of each.

  4. (d) Was a label used? Explain your answer.

  5. (e) Summarize the key characteristics of your data set.

Question 1.8

1.8 Summer jobs. You are collecting information about summer jobs that are available for college students in your area. Describe a data set that you could use to organize the information that you collect.

  1. (a) What are the cases?

  2. (b) Identify the variables and their possible values.

  3. (c) Classify each variable as categorical or quantitative. Be sure to include at least one of each.

  4. (d) Use a label and explain how you chose it.

  5. (e) Summarize the key characteristics of your data set.

Question 1.9

1.9 Employee application data. The personnel department keeps records on all employees in a company. Here is the information that they keep in one of their data files: employee identification number, last name, first name, middle initial, department, number of years with the company, salary, education (coded as high school, some college, or college degree), and age.

  1. (a) What are the cases for this data set?

  2. (b) Describe each type of information as a label, a quantitative variable, or a categorical variable.

  3. (c) Set up a spreadsheet that could be used to record the data. Give appropriate column headings and five sample cases.

Question 1.10

1.10 How would you rank cities? Various organizations rank cities and produce lists of the 10 or the 100 best based on various measures. Create a list of criteria that you would use to rank cities. Include at least eight variables, and give reasons for your choices. Say whether each variable is quantitative or categorical.

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Question 1.11

1.11 Survey of students. A survey of students in an introductory statistics class asked the following questions: (1) age; (2) do you like to sing? (Yes, No); (3) can you play a musical instrument (not at all, a little, pretty well); (4) how much did you spend on food last week (in dollars); (5) height.

  1. (a) Classify each of these variables as categorical or quantitative and give reasons for your answers.

  2. (b) For each variable give the possible values.

Question 1.12

1.12 What questions would you ask? Refer to the previous exercise. Make up your own survey with at least six questions. Include at least two categorical variables and at least two quantitative variables. Tell which variables are categorical and which are quantitative. Give reasons for your answers. For each variable, give the possible values.

Question 1.13

1.13 How would you rate colleges? Popular magazines rank colleges and universities on their “academic quality” in serving undergraduate students. Describe five variables that you would like to see measured for each college if you were choosing where to study. Give reasons for each of your choices.

Question 1.14

1.14 Attending college in your state or in another state. The U.S. Census Bureau collects a large amount of information concerning higher education.1 For example, the bureau provides a table that includes the following variables: state, number of students from the state who attend college, number of students who attend college in their home state.

  1. (a) What are the cases for this set of data?

  2. (b) Is there a label variable? If yes, what is it?

  3. (c) Identify each variable as categorical or quantitative.

  4. (d) Explain how you might use each of the quantitative variables to explain something about the states.

  5. (e) Consider a variable computed as the number of students in each state who attend college in the state divided by the total number of students from the state who attend college. Explain how you would use this variable to explain something about the states.

Question 1.15

1.15 Alcohol-impaired driving fatalities. A report on drunk-driving fatalities in the United States gives the number of alcohol-impaired driving fatalities for each state.2 Discuss at least three different ways that these numbers could be converted to rates. Give the advantages and disadvantages of each.