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4.7. Selection and Randomization Behavior
The information in this section is intended to supplement, not replace, the Selection and Randomization Behavior sections of IMS SS. Refer to IMS SS [1] for more details.
Implementations are required to exhibit the normative behaviors described in the SCORM Sequencing Pseudo Code (refer to Appendix C) instead of the pseudo code described in IMS SS.
The selection and randomization behavior section describes when some subset (possibly all) of a cluster’s children are selected and when (if) that subset is reordered. These processes affect the activities that are available and can be considered during the various sequencing processes.
The Select Children Process and Randomize Children Process are intended to be invoked appropriately by the LMS’s sequencing implementation, as defined by activities’ selection and randomization controls (refer to Sections 3.11: Selection Controls and Section 3.12: Randomization Controls), which may occur during or after termination behavior, during sequencing behavior or during delivery behavior. Furthermore, if an LMS performs tentative evaluations of navigation requests, the Selection and Randomization Processes may be invoked outside of the Overall Sequencing Process.
The only requirement for a SCORM-compliant LMS is that the Selection and Randomization Processes be applied consistently to the timing attributes of their related sequencing definition model elements.
Never: Never apply the Selection or Randomization Processes. All of the child activities will always be considered in the author-time-defined order.
Once: Apply the Selection or Randomization Processes once during the current sequencing session. This must occur before the cluster’s children can be considered during any sequencing behavior process. An LMS will typically apply selection and randomization to all activities with this defined timing before starting the sequencing session.
On Each New Attempt: Apply the Selection and Randomization Processes during or prior to a new attempt on the activity. To ensure that accurate and consistent sets of available children are utilized during rollup and the various sequencing behavior processes, an LMS will typically apply selection and randomization to an activity with this defined timing prior to the first attempt on the activity beginning and immediately after (during the End Attempt Process) an attempt on the activity ends.