Page 129 - Software and Systems Requirements Engineering in Practice

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C h a p t e r 4 : R e q u i r e m e n t s M o d e l i n g 97 97
• Show sample “idealized” models.
• Explain how QA will be performed.
• Define completion criteria.
• Review the draft schedule and expected participants.
The modeling sessions start with a skilled facilitator or team lead
modeling across and then down the model (see the heuristic for
breadth first modeling in the later section “The Early Modeling Effort
Should Cover the Entire Breadth of the Domain”). Once other analysts
have gained some experience with modeling sessions, they can take
over the lead and get experience as facilitators.
Sessions are usually run in the mornings, three or four times a
week. At each session, the subject area to be modeled is known in
advance and the appropriate subject matter experts or customers are
scheduled into the meeting (see Figure 4.13).
The first order of business in the modeling session is the analysis
of metrics from any automated analysis tools that were used on the
model. Also, any descriptions that were created offline are reverse-
engineered into the model. Assignments to make repairs (offline) are
done, and the elicitation sessions continue.
As modeling activities continue, no more than 5–8 people should
be present. A projector is used so that participants can see the model
under construction or review. Sessions should last no more than half a
day. At the conclusion of each modeling session, the facilitator exports
a spreadsheet from the model with artifacts and their descriptions.

Begin Modeling Session
Completed Artifact Import Previously Completed
Descriptions in Spreadsheet Artifact Descriptions

Generate Completion and
Error Metrics

Team repairs model errors and/or assigns Model
analysts to repair after the modeling session. Metrics
Completing artifact documentation
is done outside the modeling session Model Incomplete
to improve modeling productivity Areas
and documentation quality.
Extract Artifact Incomplete Artifact
Spreadsheets Descriptions in Spreadsheet

Assign Analysts to Complete
Artifact Descriptions
End Modeling Session

FIGURE 4.13 Example modeling session activities