Chapter 3 Working with Charts 127
c. Label the points that are highest
in MPG as measured by the height
above the average MPG for those with
around the same horsepower. Label
each of these points with the Model
(make sure that you select only these
points rather than all of the points—
or else you’ll wait a long time for all
of the labels to be added to the scatter
plot). What do these cars have in com-
mon? (Hint: Each does not have just
a traditional gasoline engine). Print
your chart.
d. Copy your scatter plot to a second
chart sheet. Break down the plot
by company region. Do you see a
relationship between Region and
MPG? Which region has lowest
MPG, on the average, for each given
horsepower?
e. Create a bubble plot on a separate
chart sheet with MPG on the y-axis,
horsepower on the x-axis and the size
of each bubble determined by the
price of the car.
f. Rescale the bubbles to 50% of the
default and relate the size of the price
column to the width of the bubbles.
Print the chart.
g. Is the price of the car related to the
horsepower and the gas mileage?
How? Describe the relationship and
explain why it should be expected.
Print the rescaled chart. Save your
changes to the workbook.
- Voting results for two presidential elec-
tions have been recorded for you in an
Excel workbook. The workbook contains
the percentage of the vote won by the
Democratic candidate in 1980 and 1984,
broken down by state. Graph and ana-
lyze the results.
a. Open the Voting workbook from the
Chapter03 folder and save it as Voting
Graphs.
b. Create a scatter plot of Dem1984
versus Dem1980 on a separate chart
sheet.
c. Rescale the axes so that the minimum
value for the x-axis and the y-axis is
20 and the maximum value is 60.
d. Examine the scatter plot. Does the
voting percentage in 1984 generally
follow the voting percentage from
1980? In other words, if the Demo-
cratic candidate received a large per-
centage of the vote from a particular
state in 1980, did he or she do as well
in 1984?
e. In one state, the candidate had a large
percentage of the vote in 1980 (above
55%) but a small percentage of the vote
in 1984 (about 40%). Identify this state.
e. Create a copy of the scatter plot on a
separate chart sheet. Break down this
new scatter plot by region.
f. Examine the location of the southern
states in the scatter plot. Do they fol-
low the general pattern shown by
the other points in the plot? Interpret
your answer in light of what you
know of the 1980 and 1984 elections.
(Hint: Consider whether the fact that the
1980 election involved a southern Dem-
ocratic candidate and the 1984 election
involved a midwestern Democratic
candidate caused a change in the voting
percentages of the southern states.)
g. Save your workbook and write a
report summarizing your conclusions.
