Chapter 1
Relationships





1.1 Related Variables

Problems

  1. Table P1 repeats the falling body data from Checkpoint 2. Do these data agree or disagree with what you think should happen to a falling object? If there are discrepancies with what you think should happen, how do you think those discrepancies might arise in the process of data gathering?

    Table P1   Falling body data
    Time
    (seconds)
    Distance
    (centimeters)
     
    Time
    (seconds)
    Distance
    (centimeters)
    0.16
    12.1
     
    0.57
    150.2
    0.24
    29.8
     
    0.61
    182.2
    0.25
    32.7
     
    0.61
    189.4
    0.30
    42.8
     
    0.68
    220.4
    0.30
    44.2
     
    0.72
    254.0
    0.32
    55.8
     
    0.72
    261.0
    0.36
    63.5
     
    0.83
    334.6
    0.36
    65.1
     
    0.88
    375.5
    0.50
    124.6
     
    0.89
    399.1
    0.50
    129.7
         

Most of the remaining problems require graph paper. Click on the image at the right to open a PDF file from which you can print your own graph paper. Start each exercise by labeling and scaling your axes in a way that is reasonable for that exercise. Use a full sheet of graph paper for each problem. (You may save the PDF file for future use.)

For Problems 2-12, do the following:

  1. Make a scatter plot of the data in the given table.
  2. Describe the shape of the graph.
  3. Explain what the shape of the graph indicates about the relationship between the variables.

  1. Table P2   Related variables
    `x`
    0.8
    1.5
    3.2
    2.6
    1.9
    2.4
    3.5
    0.6
    2.1
    `y`
    0.7
    2.1
    10.5
    6.8
    3.5
    5.9
    12.4
    0.3
    4.3


  2. Table P3   Distance traveled by a falling object
    Time (seconds)
      1
      2
      3
      4
      5
      6
      7
      8
      9
     10
    Distance (meters)
      5
     19
     44
     78
    123
    176
    240
    313
    396
    489


  3. Table P4   Parcel Post Local Rates
     Weight Not
    Over (pounds)
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    Postage
    (US dollars)
    4.38
    4.72
    5.05
    5.35
    5.63
    5.88
    6.02
    6.12
    6.23
    6.33


  4. Table P5   Temperature and pressure of a gas in a closed container
     Temperature (°K)
    263
    268
    278
    293
    298
    303
    308
    313
    323
    Pressure (mm Hg)
    752
    755
    777
    811
    834
    840
    854
    892
    906


  5. Table P6   Exports to Mexico from the United States
    Source: R. H. Ojeda et al., "North American Integration
    Three Years After NAFTA
    ," UCLA, 1996
    Year
    1987
    1988
    1989
    1990
    1991
    1992
    1993
    1994
    1995
    1996
    Exports
    (billions
    of dollars)
    20.49
    20.55
    22.84
    26.84
    42.69
    46.20
    51.89
    60.88
    79.54
    90.94


  6. Table P7   Imports from Mexico to the United States
    Source: R. H. Ojeda et al., "North American Integration
    Three Years After NAFTA
    ," UCLA, 1996
    Year
    1987
    1988
    1989
    1990
    1991
    1992
    1993
    1994
    1995
    1996
    Imports
    (billions
    of dollars)
    13.31
    20.27
    25.44
    31.27
    49.97
    62.13
    65.37
    79.35
    72.45
    82.68


  7. Table P8   Victims of Murder by Firearms in the U. S.
    Source: FBI, "Crime in the United States 2002"
    Year
    1998
    1999
    2000
    2001
    2002
    Victims
    9,220
    8,480
    8,661
    8,890
    9,369


  8. Table P9   Monthly ATM Transactions in the United States
    Source: Congressional Budget Office, "The market for ATM Services," Chapter II in
    COMPETITION IN ATM MARKETS: ARE ATMs MONEY MACHINES?, July, 1998
    Year
    1988
    1989
    1990
    1991
    1992
    1993
    1994
    1995
    1996
    1997
    ATM Transactions
    (millions)
    373.4
    426.4
    479.3
    534.9
    600.5
    642.1
    704.5
    807.4
    890.3
    915.0


  9. Table P10   Monthly Point-of-Sale Debit Card Transactions in the United States
    Source: Congressional Budget Office, "The market for ATM Services," Chapter II in
    COMPETITION IN ATM MARKETS: ARE ATMs MONEY MACHINES?, July, 1998
    Year
    1988
    1989
    1990
    1991
    1992
    1993
    1994
    1995
    1996
    1997
    POS Transactions
    (millions)
    7.4
    9.2
    12.4
    17.6
    23.3
    32.2
    45.9
    57.0
    75.4
    120.2


  10. Table P11   Average Player Salaries for the New York Yankees
    Source: ESPN, "Average Salaries from 1998-2005"
    Year
    1998
    1999
    2000
    2001
    2002
    2003
    2004
    2005
    Avg. Salary
    (millions
    of dollars)
    2.229
    3.216
    3.656
    3.930
    4.903
    4.687
    6.382
    7.391


  11. Table P12  Average Player Salaries for the Pittsburgh Pirates
    Source: ESPN, "Average Salaries from 1998-2005"
    Year
    1998
    1999
    2000
    2001
    2002
    2003
    2004
    2005
    Avg. Salary
    (millions
    of dollars)
    0.460
    0.714
    1.004
    1.292
    1.370
    1.159
    0.917
    0.964

  12. Use the data in Tables P9 and P10 to construct a table of ratios of ATM transactions to POS transactions over the years 1988 to 1997. Make a scatter plot of the information in your new table. What is the shape of the graph? What conclusions (if any) can you draw about relative growth rates of ATM and POS transactions?
  13. Make a scatter plot to analyze the relationship between rebounds and assists for the basketball data provided in Tables 2, 3, and 4. Use the graph to comment on important characteristics of the relationship.
  14. Figure P1 shows scatter plots of revenues and expenses for the Federal Employees Health Benefits (FEHB) program for fiscal years 1984 to 1996, both in billions of dollars.
    1. In which years did FEHB make a profit?
    2. In which years did FEHB lose money?
    3. What was FEHB's best financial year during the period shown?
    4. Figure P1  Federal Employees Health Benefits Program Financial Data
      Source: US Office of Personnel Management 1998 Fact Book

    1. Use the information in Figure P1 to make a table of profits for FEHB from 1984 to 1996. (Treat a loss as a negative profit.)
    2. Use your table to make a scatter plot of profits for FEHB.
    3. Find the total profit (or loss) for FEHB over the entire period shown.
Image credit
Go to Back One Page Go Forward One Page

Go to Contents for Chapter 1Contents for Chapter 1