4
Task Chapter 1
Using the data from Chapter 2 (which you should have saved, but if you didnt
re-enter it) plot and interpret the following graphs:
An error bar chart showing the mean number of friends for students and lecturers.
An error bar chart showing the mean alcohol consumption for students and
lecturers.
An error line chart showing the mean income for students and lecturers.
An error line chart showing the mean neuroticism for students and lecturers.
A scatterplot (with regression lines) of alcohol consumption and neuroticism
grouped by lecturer/student.
A scatterplot matrix of alcohol consumption, neuroticism and number of friends.
Answer;
An error bar chart showing the mean number of friends for students and lecturers. First
of all access the Chart Builder and select a simple bar chart. The y-axis needs to be the
dependent variable, or the thing youve measured, or more simply the thing for which
you want to display the mean. In this case it would be number of friends, so select this
variable from the variable list and drag it into the y-axis drop zone ( ). The
x-axis should be the variable by which we want to split the arousal data. To plot the
means for the students and lecturers, select the variable Group from the variable list and
drag it into the drop zone for the x-axis ( ). Then add error bars by selecting
in the Element Properties dialog box. The finished Chart Builder will look
like this:
The error
We can conclude that, on average, students had more friends than lecturers.
An error bar chart showing the mean alcohol consumption for students and lecturers.
Access the Chart Builder and select a simple bar chart. The y-axis needs to be the thing
weve measured, which in this case is alcohol consumption, so select this variable from
the variable list and drag it into the y-axis drop zone ( ). The x-axis should be
the variable by which we want to split the arousal data. To plot the means for the students
and lecturers, select the variable Group from the variable list and drag it into the drop
zone for the x-axis ( ). Add error bars by selecting in the Element
Properties dialog box. The finished Chart Builder will look like this:
The error bar chart will look like this
We can conclude that, on average, students and lecturers drank similar amounts, but the
error bars tells us that mean the is a better representation of the population for students
than for lecturers (there is more variability in lecturers drinking habits compared to
students).
An error line chart showing the mean income for students and lecturers. Access the Chart
Builder and select a simple line chart. The y-axis needs to be the thing weve measured,
which in this case is income, so select this variable from the variable list and drag it into
the y-axis drop zone ( ). The x-axis should again be students vs. lecturers, so
select the variable Group from the variable list and drag it into the drop zone for the
x-axis ( ). Add error bars by selecting in the Element Properties
dialog box. The finished Chart Builder will look like this:
The error line chart will look like this
We can conclude that, on average, students earn less than lecturers, but the error bars tells
us that the mean is a better representation of the population for students than for lecturers
(there is more variability in lecturers income compared to students).
An error line chart showing the mean neuroticism for students and lecturers. Access the
Chart Builder and select a simple line chart. The y-axis needs to be the thing weve
measured, which in this case is neurotic, so select this variable from the variable list and
drag it into the y-axis drop zone ( ). The x-axis should again be students vs.
lecturers, so select the variable Group from the variable list and drag it into the drop
zone for the x-axis ( ). Add error bars by selecting in the Element
Properties dialog box. The finished Chart Builder will look like this:
The error
The error line chart will look like this
We can conclude that, on average, students are slightly less neurotic than lecturers.
A scatterplot with regression lines of alcohol consumption and neuroticism grouped by
lecturer/student. Access the Chart Builder and select a grouped scatterplot. It doesnt
matter which way around we plot these variables, so lets select alcohol consumption
from the variable list and drag it into the y-axis drop zone, and then drag
neurotic from the variable list and drag it into the drop zone. We then need
to split the scatterplot by our grouping variable (lecturers or students), so select Group
and drag it to the drop zone. The completed Chart Builder dialog box will look
like this:
Click