i*

i* is an approach developed by Eric Yu and John Mylopoulos for modelling the organizational context of a software system.  Recent work with i* has been done by Neil Maiden and others. 

i* diagram key

Figure 1.  i* diagram key

i* diagrams

The nodes and edges in i* diagrams appear in Figure 1

Table 1.  Allowed connections (Under Construction)
Source node Edge Destination node
goal, task means-endgoal, soft goal
resource means-endsoft goal
soft goal contribute-to (+ or −)soft goal

Strategic dependency (SD)

A strategic dependency diagram relates actors with needs (“dependers”) to actors with the capability of meeting those needs (“dependees”).  The relations are expressed with dependency edges.  The needs are expressed in terms of goals.  Yu and Mylopoulos use “dependum” to refer to what is needed. 

Strategic rationale (SR)

A strategic rationale diagram describes how actors may achieve goals through tasks.  Subtasks are linked to their supertasks by task-decomposition edges.  Alternative ways of accomplishing a task are linked to the tasks by means-end edges. Subgoals are linked to the goal they help achieve by contribute-to edges. 

References

Maiden+Manning+2005-grsm
N. A. M. Maiden, S. Manning, S. Jones, and J. Greenwood.  Generating requirements from systems models using patterns: a case study.  Requirements Engineering, 10(4):276–288, 2005. 
Abstract
doi:10.1007/s00766-005-0010-9
Yu+Mylopoulos1994-erar
Eric S. K. Yu and John Mylopoulos.  From E-R to ‘‘A-R’’ — Modelling Strategic Actor Relationships for Business Process Reengineering.  In ER ’94: Proceedings of the13th International Conference on the Entity-Relationship Approach, pages 548–565, 1994. 
Abstract
pdf
Yu+Mylopoulos1997-embr
Eric S. K. Yu and John Mylopoulos.  Enterprise modelling for business redesign: the i* framework.  SIGGROUP Bulletin, 18(1):59–63, 1997. 
Abstract
doi:10.1145/271159.271180 url

The i* wiki

Valid XHTML 1.0 Strict
Valid CSS!
2010May16Su21:42
Thomas A. Alspaugh