Chapter 2: Graphs, Charts, and Tables--Describing Your Data

38 CHAPTER 2 • GRAPHS, CHARTS, AND TABLES—DESCRIBING YOUR DATA
FIGURE 2.1
Excel 2007 Output—
Nike Shoes Frequency
Distribution
Excel 2007 Instructions:
1. Open File: SportsShoes.xls.
2. Enter the Possible Values
for the Variable; i.e., 0, 1,
2, 3, 4, etc.
3. Select the cells to contain
the Frequency values.
4. Click on the fx button.
5. Select the Statistics—
FREQUENCY function.
6. Enter the range of data
and the bin range (the cells
containing the possible
number of shoes).
7. Press ctrl-shift-enter to
determine the frequency
values.
you own?” A total of 230 people completed the survey; Table 2.6 shows the responses to
the DVD ownership question. These data are discrete, quantitative data. The values range
from 0 to 30.
The manager is interested in transforming these data into useful information by constructing
a frequency distribution. Table 2.7 shows one approach where the possible values
for the number of DVD movies owned is listed from 0 to 30. While this frequency distribution
is a step forward in transforming the data into information, because of the large
number of possible values for DVD movies owned, the 230 observations are spread over a
large range, making analysis difficult. In this case, the manager might consider forming a
grouped data frequency distribution by organizing the possible number of DVD movies
owned into discrete categories or classes.
The first step in constructing a grouped frequency distribution is to sort the quantitative
data from low to high. The sorted data is called a data array. Next, define the classes
FIGURE 2.2
Minitab Output—Nike
Shoes Frequency
Distribution
Minitab Instructions:
1. Open file: SportsShoes.MTW.
2. Choose Stat > Tables >
Tally Individual Variables.
3. In Variables, enter data
column.
4. Under Display, check
Counts.
5. Click OK.
The number of
pairs of Nike
shoes owned.