User Guide

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Chapter 10
Figure 10-8
Select Cases Random Sample dialog box
You can select one of the following alternatives for sample size:
 Approximately. A user-specified percentage. This option generates a random
sample of approximately the specified percentage of cases.
 Exactly. A user-specified number of cases. You must also specify the number of
cases from which to generate the sample. This second number should be less
than or equal to the total number of cases inthedatafile.Ifthenumberexceeds
the total number of cases in the data file, the sample will contain proportionally
fewer cases than the requested number.
Selecting a Time Range or Case Range
To select a range of cases based on dates, times, or observation (row) numbers:
E Select Basedontimeorcaserangeand click Range in the Select Cases dialog box.
This opens the Select Cases Range dialog box, in which you can select a range
of observation (row) numbers.