Introduction to a variety of useful statistical ideas and techniques - Improving the User Experience through Practical Data Analytics - page 26

FIGURE 1.19
SPSS output for Explore, with conidence interval “arrowed.”
The above output gives us the conidence interval directly. It is 3.9195---------
4.7472 (see the two arrows in Figure 1.19 ). The difference between these value and
those obtained from Excel is simply rounding. From a usability perspective, life just
got easier. In Excel, you needed to do some basic arithmetic (getting the values of “e”
and “X-bar” separately, and needing to subtract and add the “e” to the X-bar), while
we are spared even that here in SPSS.
SIDEBAR: HOW TO DISPLAY CONFIDENCE INTERVALS ON A BAR CHART
IN SPSS
As we mentioned early in this chapter, we always like to augment any bar chart of means (either
alone or against one another) with “error bars” to represent the conidence intervals. We showed you
how to do it in Excel; now try it in SPSS. We'll use the sample data, which is simply a data set
of likelihood of adoption ratings for two different designs.