User Guide

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Chapter 7
Active Generator. Two different random number generators are available:
 SPSS 12 Compatible. The random number generator used in SPSS 12 and previous
releases. If
you need to reproduce randomized results generated in previous
releases based on a specified seed value, use this random number generator.
 Mersenne Twister. A newer random number generator that is more reliable for
simulation purposes. If reproducing randomized results from SPSS 12 or earlier
is not an iss
ue, use this random number generator.
Active Gene
rator Initialization.
The random number seed changes each time a
random number is generated for use in transformations (such as random distribution
functions), random sampling, or case weighting. To replicate a sequence of random
numbers, s
et the initialization starting point value prior to each analysis that uses the
random numbers. The value must be a positive integer.
Figure 7-4
Random Num
berSeeddialogbox
To select the random number generator and/or set the initialization value:
E From the menus choose:
Transform
Random Number Generators