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© Colin Potts B1-2
The role of systems in organizations
An organization is the context for the system’s functions» Organization provides rationale for system
Some theoretical perspectives on organizations view them as systems» Sociotechnical systems theory» IS design is mixture of Human Activity System (HAS) redesign & technical design
HAS1 HAS2 IS
© Colin Potts B1-3
Overview: SSM & BPR
Soft Systems Methodology (SSM)» A methodology for
understanding a HAS and stating recommendations for change
» Not specific to IS» Analysis of HAS
“pushes” change» Origins in STS action
research
Business Process Reengineering (BPR)» Philosophy of HAS
improvement; not a single methodology
» HAS is a collection of controllable processes
» Technology may “pull” HAS redesign
» Origins in Quality-Improvement movement practice
© Colin Potts B1-4
Soft systems methodology
Collection (not rigid sequence) of interlinked analysis activities
Outward-directed(“real-world”) activities
Inward-directed(“systems”) activities
Problem situationunstructured
Problem situationexpressed
Rootdefinitions
Conceptualmodels
Real-world/systemcomparison
Feasible/desirablechanges
Implementation
© Colin Potts B1-6
CATWOE: stakeholder types
The HAS is described in terms of six key attributes:C = Client/customer (Who are beneficiaries of HAS?)
A = Actors (Who perform activities within the HAS?)
T = Transformation (What does the HAS do?)
W = Weltanschauung / worldview (What are the key assumptions behind the HAS?)
O = Owner (Who owns the HAS and can cause it to cease?)
E = Environment (What constraints exist on how the HAS works?)
© Colin Potts B1-7
CATWOE Example:Meeting scheduling
C: Senior mgt. & office workers A: Office workers & admin. assts. T: Satisfy time utilization for
teamwork W: Busy people; coordination a pain O: Senior mgt. / IS dept. E: Calendar; corporate values
© Colin Potts B1-8
Writing a root definition
Textual definition of HAS working in CATWOE attributes:A system, owned by senior management and
the IS department, operated by office workers and administrative assistants to utilize their time effectively for teamwork within the constraints of the calendar and corporate values.
© Colin Potts B1-9
Conceptual modeling in SSM
Model what is “systemically desirable”» Informal flow diagram
callmtg
identifyprefs
monitor& control
timemake
resourcesavailable
negotiateschedule
needtomeet
indiv.workingprefs.
calendar
resourceconstraints
© Colin Potts B1-11
Comparing the model with the world
Does the systemically desirable HAS correspond to the real-world HAS?» E.g. is conceptual model consistent with rich
picture?– obviously not a formal analysis process
» If not, where can improvements be made?– SSM does not have methods for reaching
consensus on change
» and what should an IS do to improve HAS?
© Colin Potts B1-12
Team Exercise: “Quick-and-dirty” SSM
For the example system:» As a class:
(1) discuss the HAS context» In teams of 2-3:
(2) Draw a rich picture
(3) Discuss & write root definition for HAS
(4) Draw a conceptual model (top level)
(5) Identify v. high-level IS requirements» As a class:
(6) Discuss what you produce
© Colin Potts B1-13
SSM: How to find out more
Several books.» Checkland & Scholes: Soft Systems
Methodology in Action– Classic, but not specific to IS
» Patching: Practical Soft Systems Analysis– More of an action guide
» Stowell & West: Client-Led Design– Specific to IS, but not strictly SSM
© Colin Potts B1-14
Business process reengineering (BPR)
Basic thesis: an organization operates through a series of processes» Repeatable activities, roles, procedures & rules» Processes can be modeled, supported &
“enacted”
HAS is improved by redesigning processes
Scope of improvement
Local optimization
(e.g. TQM)
Radical redesign
(e.g. BPR)
© Colin Potts B1-15
The role of IS in BPR
Needs “pull” vs. technology “push”Process
“What”
“How”
possible IS
identify howIS cansupportprocess
“How” potentialtechnology
“Where”
Candidateprocesses
select processesthat technology cansupport
© Colin Potts B1-16
Organizational use cases
Use case = standard interaction between system and its environment» For an organizational use case, the system
is a HAS, envt. is the business envt. Dual models (same concepts used)
» “is”: how things are done» “ought”: envisioned improvement
© Colin Potts B1-17
Example use cases for library
memberof public
librarian
publisher....
circulation
membership mgt.
stock mgt.
© Colin Potts B1-18
Categories of business object
interface object performs tasks thatcommunicate withenvironment
e.g. customerservice assistant
control object coordinates part ofthe process
e.g. shelf stocker
entity object things handled inthe business
e.g. book
© Colin Potts B1-19
Example object model
E.g. borrowing a book
memberof public
customer serviceassistant
borrowingpolicy
librarypatron
book
© Colin Potts B1-20
Interaction diagramsCust. Svc.asst.
Borrowingpolicy
Patron Book
Member of public presents books
Customer service assistant checks membership card
Borrowing policy checks that member of public is library patron in good standing
Customer service assistant records books to be borrowed
Borrowing policy updates book record
Customer service assistant tells borrower due date
© Colin Potts B1-21
Envisioning new processes
Consider possible use cases in an IS-supported HAS» Use analogies» Standard optimizations
For example» How is a library like a gas station?
– Borrowing stations like gas pumps?
» Remove assistant by having unattended check-out station
© Colin Potts B1-22
Team exercise: BPR use cases
For the standard example:» as a class:
(1) Decide on a single business process
» in groups of 2-3:(2) Identify & categorize objects for process
(3) Draw an interaction diagram
(4) Envision new system & describe to class
© Colin Potts B1-23
BPR: How to find out more
Several books» Hammer & Champy: Reengineering the
Corporation» Morris & Brandon: Reengineering your
Business» Johansson et al: Business Process
Reengineering» Jacobson et al: The Object Advantage