Biplot basics - Understanding Biplots - page 65

50% bags 75% bags

90% bags 99% bags

31 to 40 yrs
41 to 50 yrs

51 to 60 yrs
Older than 60

Younger than 30 yrs

Figure 2.42 Biplots with selected α -bags of the mail order catalogue data set. The
α -bags demarcate the deepest 100 α % of the respondents in the different age groups.

equip the Figure 2.28 biplot with user-specified α -bags. Figure 2.42 shows this with
0.50-, 0.75-, 0.90- and 0.99-bags. Plotting of individual sample points as well as the axes
has been suppressed but the user can interactively add sample points, means, or axes
as required.
A detailed discussion with illustrations of the capabilities of PCAbipl and related
biplot functions contained in UBbipl is given in Chapter 3 where a closer look is taken
at PCA biplots.