124 Excel
c. Break the scatter plot points into
two categories on the basis of gen-
der. Does the plot suggest that male
salaries tend to be higher than female
salaries for comparable years of
employment?
d. Examine the list of other variables
in the workbook. Are there other
variables in that list which should be
taken into account before coming to
a conclusion about the relationship
between gender and salary?
e. Save your workbook and write
a report summarizing your
observations.
- Admission decisions to colleges
are often partly based on ACT math
scores and high school rank with the
expectation that these scores are related
to success in college. Is this always the
case and is gender a factor? You’ve been
provided with a data set to investigate
this question. The data set contains
columns for gender, high school rank
(HS Rank), American College Testing
Mathematics test score (ACT Math), and
an algebra placement test score (Alg
Place) from the fi rst week of class and
the fi nal fi rst semester calculus grades
(Calc) for a group of students [see Edge
and Friedberg (1984)]. Graph the data to
investigate what kind of relationships
appear to exist between the variables.
a. Open the Calculus workbook from
the Chapter03 folder and save it as
Calculus ACT Charts.
b. Create a scatter plot, on a separate
chart sheet, plotting Calc on the y axis
and ACT Math on the x axis. Label
the axis appropriately. How strong
does the relationship between the
ACT Math score and the fi rst semester
calculus score appear to you?
c. Break down the scatter plot by gender.
Is there evidence of a difference in
calculus scores based on gender?
d. Repeat steps a through c for a scatter
plot relating calculus grades to the
algebra placement test.
e. Save your workbook and then write
a report summarizing your fi ndings.
- You’ve been given a data set contain-
ing the mass and volume measurements
from eight chunks of aluminum as
recorded in a high school chemistry lab.
Graph and examine their fi ndings.
a. Open the Aluminum workbook from
the Chapter03 folder and save it as
Aluminum Chart.
b. Create a scatter plot with mass values
on the y axis and volume values on
the x axis. Add major gridlines for
both the x axis and the y axis.
c. Examine your chart. There should be
a data value that appears out of place.
Mark this point by changing the plot
symbol used for that point to a differ-
ent color from the rest of the points.
d. Do the other points seem to form
a nearly straight line? The ratio of
mass to volume is supposed to be a
constant (the density of aluminum),
so the points should fall on a line
through the origin. Draw the line,
and estimate the slope (the ratio of
the vertical change to the horizontal
change) along the line. What is your
estimate for the density of aluminum?
e. Save your workbook and write a
report summarizing your fi ndings. - You’ve been asked to investigate the
relationship between protein and carbo-
hydrates in several brands of wheat cere-
als and breads. Data taken from a trip to
a local grocery store has been recorded
and saved for you.
a. Open the Wheat workbook from the
Chapter03 folder and save it as Wheat
Charts.
b. Create a scatter plot with Protein on
the y axis and Carbo on the x axis.