
Analysis and visualization tools 543
in which sets of 1 0 genes can have one of 5 different behaviors described be low.
This example was originally created by John Quackenbush.
7
EXAMPLE 17.2
This artificial time s eries data set will include “ genes” from each of the fol-
lowing categories:
Are relatively constant:
– around zero
– at some positive value
– at some negative value
Increase steadily
Decrease steadily
Oscillate
– up then down then up around a positive, zero or negative value
– down then up then down around a positive, zero or negative value
In total, there are nine such typical gene profiles shown in Fig. 17.22. A
number of other genes are create