1 soft systems method an introduction methods for information systems development soft systems...
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Soft Systems Method An Introduction
Methods for Information Systems Development
Soft Systems Ideas
Overview of Soft Systems Method
Rich Pictures
Relevant Systems and Root Definitions
Conceptual Modelling
Bringing About Change
2
Information Systems Methods
Structured Methods:
• Yourdon, SSADM, Information Engineering
Object Oriented Methods:
• OOSE, OMT, Rational (UML)
RAD Methods
• DSDM
‘Bottom Up’ Evolution: Programming, Design,
Analysis, . . . .
All Based On Sound ‘Engineering’ Principles:
• i.e. First Know Requirements then Build a System
3
Computer
Division
Problem Situation: Often ‘Out of Stock’ of Products Sold
Solution: Computerise Production Planning
Result: Company Closure
A Cautionary TaleManaging Director
Finance
Division
Sales
Administration
R & DMarketing
Division
Sales Division
Production
Division
Activities:1 Forecast Sales2 Buy Materials3 Manufacture4 Sell5 Deliver
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Types Of System
DESIGNED PHYSICAL SYSTEMS, e.g. Bridge,
Aircraft, Channel Tunnel, Power Station
COMPONENT PARTS are Physical Components
HUMAN ACTIVITY SYSTEMS (HAS), e.g. An
Information System
COMPONENT PARTS are Physical Components
but also Humans Performing Tasks
IS Methods Are Based on Same Principles as
Building DESIGNED PHYSICAL SYSTEMS, But . .
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An HAS is More Than A Set of Activities
SOCIAL SYSTEMPLUS
HUMAN ACTIVITY SYSTEM
SYSTEM OF
ACTIVITIESEQUALS
TRANSFORMATION PROCESS
(Modelled as an Interconnected Set
of Activities)
Input(s) Output(s)
Elements = Activities (or sub-systems), i.e. “WHAT”
Relationships = Logical Dependencies
Elements = People Doing Activities, i.e. “HOW”
Relationships = Inter-Personal
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PROBLEM SITUATIONS
HARD May Be Analysed as a
‘Designed Physical System’ and Modelled
Mathematically
SOFTMay be Analysed As a Set of HASs
where Modelling Language Consists of
Activities (Verbs) but . . . Can We Ignore
Inter-Personal Relationships?
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Aims of Soft Systems Method
SSM is NOT a Method for Developing an Information
System
SSM Aims to Bring About ‘Improvement in a Problem
Situation’
To Develop an Information System, Requirements Have
to Be Established and Agreed
SSM Could be Used to Help People ‘Agree on the
Requirements’
If Requirements are Unclear, SSM Could Be a Front End
for a DSDM (or Other Method) Development
But, It May (or Even More Likely) Result in Change that
Does Not Require the Building of an IS
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Soft Systems Ideas PROBLEMS Do Not Have an Existence Independent of
the Humans Involved With Them
People Will See the Same Situation in Different Ways
"Filter"
WObservation OfReal World Events
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Soft Systems Ideas PROBLEMS Do Not Have an Existence Independent of
the Humans Involved With Them
People Will See the Same Situation in Different Ways
If ‘Problems’ are Intellectual Constructs then so should
be ‘Solutions’
Problems do not exist in Isolation
Improvements in a Problem Situation Are Most Likely to
Come About Through Persuasion and Debate
The Analyst is a ‘Catalyst of Change’ and cannot be
divorced from the situation.
"Filter"
WObservation OfReal World Events
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SOFT SYSTEMS METHOD
3. RELEVANT SYSTEMS AND ROOT DEFINITIONS
RS 1
RS 2
RS 3
RD 1
4. CONCEPTUAL MODEL
ABSTRACT
WORLD OF
SYSTEMS
THINKING
7. IMPLEMENT CHANGES
6. DEBATE ON FEASIBLE
AND DESIRABLE CHANGES
2. THE SITUATION ANALYSED
Rich Picture
Issue 1
Issue 2
Primary Task
REAL WORLD
1. THE PROBLEM
SITUATION UNSTRUCTURED
5. COMPARISON OF
4 WITH 2
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ANOTHER VIEW OF SSMStep 2 - Look At The Complex Situation. Represent Its Complexity, Without Jumping to Conclusions About the ‘Type’ of Situation or the Nature of the Problem
Step 7 - Implement Agreed Changes
Step 4 - Build a Model of the ‘Relevant System’ (Issue or Task-based). What Will the System Logically Have to Do If It Were the System Defined
Step 6 - Discuss the Consequence and Agree Changes (Defined by Those Involved - NOT the Analyst)
REAL WORLD
Step 5 - Compare the Model With the Actual Situation
REAL WORLD
Step 3 - View the Situation in Terms of a ‘Relevant System’ (Issue or Task-based)ABSTRACT
WORLD OFSYSTEMSTHINKING
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SSM - STAGE 1 ENQUIRY Begins With A ‘Mess’ OR ‘ A Setting Where Someone
Thinks a Problem May Exist
Resist Attempts to Impose a Particular Structure on the
Situation
Recognise That You Will Become Part of the Situation
Do Some Thinking About the Following Roles:
Make Practical and Administrative Arrangements,
E.G. Negotiate Access to People, Locations, …Arrange a
Quiet Office. Determine Method of Recording Information
From Interviews
The
Problem
Solver
The
Client
The
Problem
Owner
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SSM - STAGE 2‘The Situation Analysed’
Conduct Interviews. Draw a Rich Picture
Guidelines:
Look for Elements of Structure of the Situation
Look for Elements of Process
Look for Interaction of Structure and Process
Do Not Try and Represent the Situation in Terms of
Systems.
Ensure Your Picture Includes ‘Hard’ Factual and ‘Soft’
Subjective Information
Look at Social Roles. Try and Identify ‘Good’, ‘Bad’, and
‘Acceptable’ Behaviour.
Annotate Picture With Footnotes
Include Yourself in the Picture
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RICH PICTURE - SOAP ‘n’ SPRAY
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RICH PICTURE - ALBION MILLS
Courtesy Open University
16
SOFT SYSTEMS METHOD
3. RELEVANT SYSTEMS AND ROOT DEFINITIONS
RS 1
RS 2
RS 3
RD 1
4. CONCEPTUAL MODEL
ABSTRACT
WORLD OF
SYSTEMS
THINKING
7. IMPLEMENT CHANGES
6. DEBATE ON FEASIBLE
AND DESIRABLE CHANGES
2. THE SITUATION ANALYSED
Rich Picture
Issue 1
Issue 2
Primary Task
REAL WORLD
1. THE PROBLEM
SITUATION UNSTRUCTURED
5. COMPARISON OF
4 WITH 2
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SSM - STAGE 3 ‘Relevant Systems’
A Systemic Way of Viewing the Situation Which Is (in the
opinion of the analyst), in Some Way, Relevant to the
Problem Situation
When Described in More Detail It Is Hoped That Studying
the Abstract System Will Yield Insight Into the Situation
Relevant Systems May Be of Two Types:
Issue-based - Will Focus on Specific Issues and Seek to
Address or Act Upon Them in Some Way
Task-based - Are Attempts to Describe, or Capture, the
Essential Nature of a Fundamental Task Which Must Be
Carried by the Organisation Under Study
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SSM - STAGE 3 ‘Root Definitions’
DEFINITION - A Precise Verbal Description of the Essence
of the Processes Implied by the RELEVANT SYSTEM
EXAMPLE “A SOAP’N’SPRAY Owned System Engaged in
the Manufacture and Supply of Soap Products to Satisfy
Customers’ Orders in a Way That Is Consistent With
Performance Levels Desired by Corporate Headquarters”
A Relevant System Is a ‘System’. Hence It Must Conform
to ‘Systems Theory’
It May Help to Consider a CATWOE Analysis
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CATWOE Analysis of SOAP’N’SPRAYC- CUSTOMERS of the System
Those Who Order Soap Products (European, Retailing, Commercial and
Industrial Markets)
A - ACTORS
Those Who Carry Out the Manufacture and Supply Activities
T - TRANSFORMATION PROCESS
Transform Vegetable Oil (and Other RMs, If Needed) Into Finished
Soap Products and Supply to Customers
W - WELTANSCHAUUNG
A Concern to Meet Orders Whilst Achieving Financial Targets Set by
HQ
O - OWNERS
SOAP’N’SPRAY (Note: the owners of the relevant system, not the
business)
E - ENVIRONMENTAL CONSTRAINTS
The Business and Commercial Competitive Environment
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SOFT SYSTEMS METHOD
3. RELEVANT SYSTEMS AND ROOT DEFINITIONS
RS 1
RS 2
RS 3
RD 1
4. CONCEPTUAL MODEL
ABSTRACT
WORLD OF
SYSTEMS
THINKING
7. IMPLEMENT CHANGES
6. DEBATE ON FEASIBLE
AND DESIRABLE CHANGES
2. THE SITUATION ANALYSED
Rich Picture
Issue 1
Issue 2
Primary Task
REAL WORLD
1. THE PROBLEM
SITUATION UNSTRUCTURED
5. COMPARISON OF
4 WITH 2
21
SSM - STAGE 4 ‘Conceptual Models’
A Model of the Activities or Processes That Logically
Ought To Go On If the Relevant System Is to Be the
One Described by the Root Definition
A1
A2A3
A4
A5
A6A7
A8
A10A9
A GENERALISED CONCEPTUAL MODEL
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Conceptual Model - Guidelines
Activities are Represented by VERBS
Arrange into a Logically coherent Order
Aim for 6 to 12 Activities for a Complete Account
Examine Each Main Activity and Identify Subsidiary
Activities, Each Written Down As a Verb
Group Functionally Similar Activities into Sub-
Systems
Remember It Is a Logical Model - No Real-World
Considerations
If Necessary, Revise the Root Definition
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SSM - STAGE 4 ‘Conceptual Model’
FRONT LINE ACTIVITIES:
RECEIVE Customer Orders for Soap Products
KNOW Performance Levels Required by HQ
MANUFACTURE Soap Products
OBTAIN Raw Materials
DISTRIBUTE Soap Products
PLAN Operations Needed to Meet Orders
MONITOR & CONTROL
All the Above Activities
"A SOAP'N'SPRAY - Owned System Engaged in the Manufacture and Supply of Soap Products to Satisfy Customers' Orders in a Way that is Consistent with the Performance Levels Desired by Corporate Headquarters."
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Conceptual Model - SOAP ‘N’ SPRAY
KNOW HQ's
Requirements
PLAN Operations
RECEIVE Customer
Orders
MONITOR & CONTROL
All Activities
MANUFACTURE Soap
Products
OBTAIN Raw Materials
DISTRIBUTE Soap
Products
FIRST STAGE MODEL
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Conceptual Model - SOAP ‘N’ SPRAY
RECEIVE Purch. Reqs
KNOW Buying Pol'y
DECIDE Where To
Obtain GoodsORDER Goods
INFORM Concerned
Groups
OBTAIN
RECEIVE Delivery Not'n
KNOW Facilities
ANALYSE Info Rec'd
RECEIVE Orders Info
DECIDE
ASSEMBLE Decisions
PLAN
TRANSMIT Info
SCHEDULE Activities
MAINTAIN Plant
MAKE Products
RECEIVE RMs
RECEIVE
MANUFACTURE
CHECK Processes &
Stds
DECIDE Schedule of Ops
TRANSPORT Products
STORE Products
COLLECT Fin'd Prods
RECEIVE Del'y Instrns
DISTRIBUTE
KNOW About Disposal
Facilities
RECEIVE Customer
Orders
MONITOR &
CONTROL All Other Activities
RECEIVE Info
ANALYSE Info
ASSEMBLE Info
INTERPRET Info
DISSEMINATE Info
KNOW
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SOFT SYSTEMS METHOD
3. RELEVANT SYSTEMS AND ROOT DEFINITIONS
RS 1
RS 2
RS 3
RD 1
4. CONCEPTUAL MODEL
ABSTRACT
WORLD OF
SYSTEMS
THINKING
7. IMPLEMENT CHANGES
6. DEBATE ON FEASIBLE
AND DESIRABLE CHANGES
2. THE SITUATION ANALYSED
Rich Picture
Issue 1
Issue 2
Primary Task
REAL WORLD
1. THE PROBLEM
SITUATION UNSTRUCTURED
5. COMPARISON OF
4 WITH 2
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SSM - STAGE 5 ‘Preparing An Agenda For Debate’
NOTES:
Some Activities may not feature on the Agenda for
Stage 6
Items 5 & 6 above may be completed as part of stage 6
Activity in CM
Exist Or Not?
Present Mechanism
Measure of Performance
Proposed Change
Comments
1 2 3 4 5 6
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SSM - STAGE 6 ‘Debate’
WHO IS INVOLVED?
Client, Problem Owner(s), Problem Solver(s), Others
AIMS
To Agree Changes That Are:Systemically DesirableCulturally Feasible
WHAT IF CHANGES CANNOT BE AGREED?
This May Be A Wise Decision in Some Circumstances
Maybe Your Chosen Relevant System Is NOT Seen As
Relevant. If So, Repeat From Stage 2.
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TYPES OF CHANGE THAT MIGHT COME ABOUT: Changes in Structure:
e.g. Organisational Groupings
Departments
Reporting Structures
Lines of Command
Lines of Functional Responsibility
Physical Layout Changes in Procedures
i.e. Different Ways of Doing Things Changes in Policy in the Goals & Strategies of the HAS
Being Investigated Changes in Attitude
SSM - STAGE 7 ‘Implementation’
30
Soft Systems MethodResume of Rules - Constitutive
Seven Stages, Many of Which Are
Iterative
Each Stage Has A Defined End-Product
CMs To Be Checked Against RD and
Formal Systems Model
CMs To Be Derived from RD Only. They
are NOT Descriptions of Systems to be
Engineered
Initial Exploration Should NOT be a
Search for Systems in the Problem
Situation