Practical exercises - Answers
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You begin by entering the data in the computer. This entails the
definition of the variable and then the entry of the data. To do the first you:
Go to SPSS
Data Editor and click Variable View
(bottom left of the screen).
Go to the
first line of the page.
Fill in all
cells of the line: when completed, the line can be as follows:
famsize - numeric - 8 - 0 - Age of children - none - none -
8 - right - Nominal.
To enter the data you 'ungroup' the figures given in the question by
bringing them back to their original state, that is, as they were identified
during the study. For instance, the study found that seven families said they
had one child. Therefore you enter '1' seven times in the column. For the same
reason you enter '2' four times, '3' two times and '4' two times. More specifically, you:
Go to SPSS Data
Editor/Data View.
Insert one by one the number of children per family under
the column title as explained above.
The data is now ready for processing.
1 Constructing the bar chart
Go to Data
Editor/Data View and click Graphs
and then Bar.
In the dialog box Bar
charts click Simple and then
activate Summary for Groups of Cases.
Then click Define.
This brings you to the dialog box Define
simple bar: Summary for Groups of Cases.
In this box click the button next to No of Cases to activate it.
In the same dialog box click the variable 'Family size
(famsize)' to highlight it, and then click the arrow that stands before Category axis to transfer this variable to the empty space below it.
Now click OK. The
bar graph is displayed on your screen as shown below.
If the graph
does not appear, repeat the process, this time more carefully.
2 Constructing the pie chart
Now
that the groundwork for the construction of graphs (data entry, etc.) is
completed, producing a pie chart is rather simple. The reason for this is that
the procedure follows the same path.
Click Graphs and
then Pie.
In this new dialog box, activate Summaries for groups of cases (if it is not activated), and then
click Define.
Activate N of Cases
(if it is not activated).
Click the triangle in front of Define slices by to transfer the variable to the space below it.
Click OK. Instantly, the pie graph is displayed on screen.
Copying charts
You may wish
to copy the chart and paste it into a Word file. Copying is done simply by
using the following steps:
Click on the chart.
Click Edit in the menu and then click Copy - the graph is
copied.
Go to the Word file in which you wish to transfer the chart.
Click Edit in the menu and then click Paste. The transfer is
completed.
The same procedure can be
employed to transfer tables to Word files.
In the first instance we must enter the data in the computer. This
process is identical to that employed in the previous question. Our variable is
'spending' and it is a scale variable. Having entered the data in the computer,
the construction is very simple. We proceed as follows:
In the Data Editor's menus select Charts and then Histogram.
This brings us to the Histogram dialog box.
In the Histogram
dialog box click the variable in the list box to highlight it.
Click the triangle in front of Variable; the variable is transferred automatically to the space
below.
Click on the box next to Display normal curve.
Click OK.
The histogram is
displayed in the Viewer window, and is as shown below.
1 Ratio: Foreign to local student ratio: foreign students = 31; local students = 425 - 31 = 394
Ratio is 31/394 = 0.0786802 = .08;
or better 0.08 x 100 = 8. This means
that there are about 8 foreign students for every 100 local students.
2 Percentage: The
percentage
of foreign students in psychology class is:
31 x 100 = 3100 / 425 = 7.3%. Hence, 7.3 percent of the psychology students
are foreign students. Similarly, the proportion of local students is 92.7%.
1 Data: Female students = 230; male students = 195
2 Ratio: Female to male ratio:
female / male = 230 / 195 = 1.18 or 1.18 x 100 = 118, that is, there are 118
female students for every 100 male students.
Male to female student ratio: 195 / 230 = 0.85 or 0.85 x 100 = 85, that
is, there are about 85 male students for every 100 female students.
3 Percentage: Male
students - 195 x 100 = 19500 / 425 = 45.9, hence the percentage of male
students is 45.9%.
Female students: 230 x 100 = 23000 / 425
= 54.1, hence the percentage of female students is 54.1%
You first define the variable ('scores'), and then enter the data in the
computer by listing one by one the scores given in the question. Following this
we proceed with the computation of the mean. This entails the following steps:
Go to Analyze/Descriptive Statistics/Frequencies.
Transfer the
variable to the Variable(s) box and
click Statistics.
In the new
dialog box activate Mean.
Click Continue and then OK.
The computer produces the following table:
Statistics
Test scores
| N | Valid |
48 |
| Missing |
0 | |
| Mean |
70.54 | |
The mean test score is shown to be 70.54. This means that the average
test score in the sociology examination was 70.54.
The computation procedure here is the same as that employed in the
previous question, with the exception that in the Frequencies: Statistics dialog box you activate not only the mean,
but also the mode and the median. This way you obtain values for all three
measures of central tendency, as shown in the table below.
Statistics
Test
scores
|
N |
Valid |
48 |
|
|
Missing |
0 |
|
Mean |
70.54 |
|
|
Median |
69.00 |
|
|
Mode |
48a |
|
a
multiple modes exist. The smallest value is shown.
Here it is shown that the
mean is 70.54, the median 69.00 and the mode 48.