Title: Present System Dynamics as methodology to
1Applying System Dynamics to Manage Dynamic
Complexity in Enterprises by Jose J Gonzalez
professor dt.techn., dr.rer.nat. AUC
Objectives
- Present System Dynamics as methodology to
- identify,
- define,
- model enterprise challenges characterized by
dynamic complexity - Communicate how system dynamic simulations serve
to - explore scenarios,
- test policies,
- identify robust strategies,
- provide insights that lead to organizational
learning - Exemplify by means of real-life cases
- (mis)managing traffic pollution
- boost and bum in semiconductor industry
- time and cost overruns in large-size projects
- erosion of security and safety standards
- dealing with volatility and uncertainty in
offshore
2Issues
- Characteristics of Enterprise Challenges
- Dynamic Complexity The Logic of Failure
- System Dynamics Methods and Applications
- Learning in Complex Domains
- Organizational Learning
3Issues
- Characteristics of Enterprise Challenges
- Dynamic ComplexityThe Logic of Failure
- System Dynamics Methods and Applications
- Learning in Complex Domains
- Organizational Learning
- Examples of Enterprise Challenges
- Analysis
- Main Conclusions
4Characteristic of Enterprise/Public Challenges
- Consider the following enterprise (or even
public) challenges - (Mis)managing traffic pollution in Mexico city
- Boom and bust in semiconductor industry
- Cost time overruns and quality problems in
large-scale projects - Ubiquitous erosion of safety security
standards, making companies and nations
vulnerable (organizational accidents, cyberwar,
terrorism) - Rig management in offshore companies
(specifically, Statoil) fronting high risks (hugh
investments per rig, volatile oil prices,
unpredictable demand, unsafe conditions, emerging
technologies)
5Characteristic of Enterprise/Public
ChallengesManaging traffic pollution
- Traffic pollution in Mexico city
- Air pollution in Mexico City is amongst the worst
in the world - The authorities decided to limit vehicle use
every car has a color-code, and for one workday a
week is banished - The expected result was a 20 reduction in car
usage on weekdays - there now seems more cars than ever, and they
seem to be producing ever increasing pollution - Link to Causal-loop analysis explains why
- Such behavior is known as policy resistance. It
is a typical outcome when planning ignores the
propagation of effects and the impact of
(counteracting) feedback.
6Policy Resistance Attempt to Control Pollution
(Courtesy Prof. Graham Winch)
Intended effect Less pollution
Unintended effect Higher car use and more
polluting cars
Unintended effect More cars
RETURN to Managing traffic pollution in Mexico
7Characteristic of Enterprise ChallengesBoom and
Bust
- Boom and bust in semiconductor industry
- An international diversified company was forced
to write down several hundred million dollars in
investments in semi-conductor capacity - New entrants were eager to capitalize on the
buoyant market, which was exaggerated by perverse
buying practices by the customers - In just a few years, that industry went from boom
to bust from acute shortage to book-to-build
ratios of only 70 at the trough - Link to Causal-loop analysis explains why
- Among the crucial errors committed was failure to
distinguish between perceived and real demand and
to account for the impact of delays
8Reference behavior for semiconductor industry
(Courtesy Prof. Graham Winch)
PHASE 1
PHASE 3
PHASE 2
Perceived demand
30
Demand
70
Capacity
FORWARD to examples of Modeling Perceptions
time
9Causal loop for semiconductor industry (Courtesy
Prof. Graham Winch)
Supply
Perceived Demand
(B) Businessexpansion
Capacity Building
Demand Gap
(R) Ghost Demand
Prices and Profits
Demand
time delay
Ghost Orders
RETURN to Boom and bust in semiconductor industry
10Characteristic of Enterprise ChallengesLarge-sca
le projects
- Cost time overruns and quality problems in
large-scale projects - Large-scale projects (e.g. design construction
of civil works infrastructure, development of
complex software or new products, military
projects) are consistently mismanaged - Typical for commercial projects 140 costs
190 time overruns - for military projects 310 costs 460 time
overruns. - Link to Famous case Ingalls Shipbuilding, USA
- Among the crucial errors committed was failure to
consider the impact of propagations of delayed
effects and to distinguish between perceived and
real project progress
11Famous CaseIngalls Shipbuilding
- John D Sterman, Business Dynamics, 2000, Ch. 2
describes case - In 1969-70 Ingalls Shipbuilding won two major
contracts to build two fleets for the US Navy - Prospects looked very profitable but a few years
later Ingalls was facing bankrupt with project
cost overruns in the order of 1.5 billion USD in
terms of year 2000 dollars - Ingalls blamed the US Navy for causing most of
the project delays by due to many changes in the
specifications - The US Navy disagreed sharply, since the changes
though numerous were of minor nature - Ingalls sued the US Navy and based its case on a
system dynamic model of the project developed by
Pugh-Robert Associates.
12Cost time overruns Ingalls ShipbuildingRef.
JD Sterman, Business Dynamics, 2000
13Cost time overruns Ingalls ShipbuildingRef.
JD Sterman, Business Dynamics, 2000
Out-of-Sequence Work, Worksite Congestion, Bad
Coordination Morale
Dashed lines NegativeFeedbacks
Burnout
KnownRework
Obsolence Rate
Solid lines PositiveFeedbacks
FORWARD to examples of modeling perceptions
14Famous CaseIngalls Shipbuilding
- John D Sterman, Business Dynamics, 2000, Ch. 2
describes result of court dispute - The system dynamic model showed, indeed, that
changes in specification were responsible for
most of the cost increase - The US Navy argued that the system dynamic model
had been manipulated to provide desired results
for Ingalls Shipbuilding - Modelers invited US Navy to criticize the model,
accepting changes when reasonable - The revised model led to even greater impact of
specification changes on costs - Hence, the US Navy accepted Ingalls claim
RETURN to Famous case
15Characteristic of Enterprise ChallengesErosion
of standards
- Ubiquitous erosion of safety security
standards, making companies and nations
vulnerable (organizational accidents, cyberwar,
terrorism) - Human failure accounts for 70-90 of
organizational accidents and security problems - but human failure must be seen as interacting
with technology and working environment. - Rich variety of causes priority conflicts, human
behavior economics, shrinkage of viable actions
as system is patched, and last not least
reinforcing of wrong attitudes modulated by risk
misperception - Link to Causal loop analysis shows why
- Crucial causes of the erosion of standards are
misperception of risk and superstitious
learning apparent (but not real) empirical
confirmation of misperceptions and wrong causal
attributions
16CLD Erosion of security safety standardsRef.
JJ Gonzalez, 1995, 2002
and since most breaches do not lead to accidents
modern technology is forgiving risk is
misperceived, implying stronger reinforcing of
noncompliance
until the inevitable mishap happens and the
lesson is learned the hard way.
but noncompliance is reinforced since it brings
personal gains
All other things being equal employees would
comply with prescriptions
RETURN to Erosion
17Characteristic of Enterprise ChallengesRig
management
- Rig management in offshore companies
(specifically, Statoil) - Hugh risky investments for rig brokers rigs
costs typically 1 billion USD, take ca. 3 yr to
build, financing groups demand, up-front 70 rig
leasing within 5 yr to cover financial risks,
emerging competing, technologies, changing safety
legislation - Users offshore companies risk volatile oil
prices (between 10 and 30 UDS pr barrel),
uncertain profitability of lots, variety of
operational conditions (tasks, climate, depth),
and large price differences between long-term and
spot rig leasing, overruns of offshore project
costs and times. - Hence, unpredictable long-term demand for rig
brokers - and unpredictable long-term supply for offshore
companies. - Analysis shows that most aspects of The Logic of
Failure are involved - Complexity challenges related to big delays,
propagation of effects, uncertain external
conditions, long time intervals up to 30 yr ,
hugh financial stakes, misperception of feedback
in short, most of the features identified as
failure factors (Dietrich Dörner The Logic of
Failure)
18Issues
- Characteristics of Enterprise Challenges
- Dynamic Complexity The Logic of Failure
- System Dynamics Methods and Applications
- Learning in Complex Domains
- Organizational Learning
- About Dynamic Complexity
- The Logic of Failure
19Dynamic Complexity The Logic of Failure
- There are two kinds of problem complexity
- Combinatorial, a.k.a. detail complexity (many
components and relationships) - Dynamic complexity (complex behavior over time)
- The major challenge is dynamic complexity, found
in non-linear systems, because it poses
tremendous challenges The unaided mind is very
poor at predicting the time development of
non-linear systems, even if they only have a few
components - Failure to deal with future developments has
crucial consequences for companies Over one
third of the Fortune 500 largest companies in
1970 had disappeared 13 years later (Arie de
Geus The Living Company)
20Dynamic Complexity The Logic of Failure
- Research by Dörner et al. about thinking,
decision-making and acting in complex domains
Most people fail and the behavior patterns are
(quite) universal but a few master complexity. - Dörner found determinants of human failure
- Linear thinking fails to account for
propagation ramification of effects - Poor ability to perceive understand feedback
(misperception of feedback, wrong causal
attribution), hence policy resistance - Ignoring time delays, wrongly assigning causes to
events close in time and space - Problems to perceive nonlinear growth and decay
- Encapsulation falling in love with a
particular aspect, ignoring other, often much
more important aspects - Thematic vagabonding unfocused, poorly
structured thinking - Etc
21Issues
- Characteristics of Enterprise Challenges
- Dynamic Complexity The Logic of Failure
- System Dynamics Methods and Applications
- Learning in Complex Domains
- Organizational Learning
- About System Dynamics
- Model development
- Modeling perceptions delays
- Structure and behavior
- Types of system dynamics models
- Integrated Solutions
22About System Dynamics
- System Dynamics is a discipline explicitly
designed to manage systems characterized by - nonlinear dynamics,
- feedback,
- time delays,
- soft factors,
- interdisciplinary aspects
- Founded 1957 by Jay W. Forrester as extension of
control theory/cybernetics to management - Later succesfully applied to all kind of complex
dynamic systems, involving psychological, social,
technological or even environmental aspects
23Qualitative System Dynamics
- Qualitative System Dynamics employs causal loop
diagrams to explain the likely mechanism of
complex phenomena, such as attempts to manage
traffic pollution in big cities or boom and bust
in high-velocity industries. - At this level, causal loop diagrams explain
cause-effect influences by an arrow pointing from
cause to effect. No indications of strength nor
or type (i.e. direct impact, cumulative impact,
etc.) of the effect are given. - Even at this simple level, causal-loop diagrams
can qualitatively explain phenomena, or even if
the causal-loop diagram is designed in advance
prevent the decision-maker from costly mistakes
and suggest better measures to manage the system. - To understand the relationship between (causal)
structure and dynamic behavior one needs
quantitative methods, i.e. System Dynamics proper.
24System Dynamics Methods
- As methodology, System Dynamics spans from
knowledge capture problem articulation to
scenario policy analysis and improvement of
organizational knowledge. - System Dynamics is best understood as an eclectic
methodology a joint venture of disciplines
borrowing methods and tools from other
disciplines and amalgamating interdisciplinary
sources of knowledge, such as - Methods Data mining, statistical parameter
estimation, econometric methods, optimization,
risk assessment management - Disciplines Nonlinear numerical methods, control
theory cybernetics, management science,
economics, psychology, group dynamics, supply
value chain science, organizational learning, - System dynamics models can be stand-alone, but
leading tool developers (High Performance
Systems, Powersim Corporation, Ventana Systems)
provide a variety of interfaces to other tools
(API, OCR, ASP, etc).
25Model development
- Model development involves the following
activities (that can be iterated) - Problem definition and articulation
- Who cares and why?
- Problem symptoms
- Desired behavior
- Policy behavior
- Audience model purpose and uses
- System boundary
- Model conceptualization
- Articulating issues, identifying variables,
sketching causal loop diagrams, formulating a
dynamic hypothesis - Designing model with software tool, e.g. Powersim
Studio - Verifying and validating model
- Tuning model
- Testing model looking for policies
- Optimization, risk assessment, risk management
- last, not least, organizational learning
26System Dynamics Stock-and-Flow Diagrams
- System dynamic models are visualized through
diagrams, the icons stocks, flows, auxiliary
variables and constants having semantic
content, i.e. specific topological and
mathematical properties.
Constants (actually parameters)
Stock, cumulated by inflows and de-cumulated by
outflows
Information links, expressing dependencies
Model sector
Flow, here an inflow
Auxiliary variables
27System Dynamics Stock-and-Flow Diagrams
- System dynamic models typically contain physical
processes, information flow, human aspects, soft
factors, formation of perceptions and
expectations and delays.
Physical processes, i.e. how staff comes in and
out of the project
Information flow, e.g. how desired workforce
affects hiring
Workforce adjustment time depends on human
decisions and market conditions
28System Dynamics Stock-and-Flow Diagrams
Formation of perception soft factors (time to
perceive productivity), soft relationships
(formation of expectation)
- System dynamic models typically contain physical
processes, information flow, human aspects, soft
factors, formation of perceptions and
expectations and delays.
Show model
29System Dynamics Modeling Perceptions and Delays
- Human behavior and decision-making is based on
perceptions of reality rather than reality
itself. - Examples
- Link to Boom and bust in high-velocity industries
- Link to Project management
- Link to Erosion of security standards
30Modeling Erosion of Security Standards
31Modeling Erosion of Security Standards
Perceived risk is out of phase with actual
(current) risk due to a perception delay. Wrong
perceptions lead to increasing actual risk.
Accidents happen with increasing probability when
current risk enters the accident zone
Accidents
32Modeling Erosion of Security Standards
Conditioning of higher compliance only occurs
during a short interval in a "risk perception
cycle." Misperception of risk and the absence of
accidents due to secure technology act during
a longer interval to de-condition desired
behavior (extinction zone).
RETURN to examples of modeling perceptions
33Modeling Perceptions
- How does a project manager assess the
productivity of staff? In a large-scale project
one has several important factors affecting
productivity - Tasks apparently completed are reported and
accepted by management as being completed
further down the road some of the tasks turn out
to be faulty and must be reclassified as rework - Existing staff experience increases, thus leading
to higher productivity - New hires dilute experience and require
counseling from experienced staff, both aspects
decreasing average productivity - All these factors generate information that
changes the project managers perception of
staff productivity. Perception can be seen as a
smoothing of information (Change in perceived
productivity) with a characteristic (individually
different) time constant (Smoothing time)
Show model
34Structures and Behavior
Structure drives model behavior over time
Issue Identification and Brainstorming
Events
Historical Results and Patterns of Behavior
Behavior
Simulation
Structure
35Feedback and Behavior
Feedback loops are linked to specific kinds of
behavior
Basic Behavior Patterns
All behavior involving feedback is made up of
combinations of these behavior patterns.
36Diverging behavior
- Created by positive feedback loops
The higher the population, the more births, which
in turn leads to increased population (over time)
Debt with compounding interest (no installments)
37Converging behavior
- Created by negative feedback loops
Production gradually empties reservior, causing
reservior pressure to drop and production to
decline
The higher the quality gets, the more difficult
it gets to increase the quality further
38Oscillating behavior
- Created by negative feedback loop involving major
delay
Inventories typically fluctuate since it takes
time before a decision to correct the inventory
will result in new products being received
(production and delivery delays).
39S-shaped behavior
- Caused by shift in feedback loop dominance from a
positive loop to a negative loop
Positive loop
Negative loop
Phase 1
Phase 2
In the first phase sales grow exponentially due
to the word-of-mouth effect. As the market gets
saturated, sales decline.
40Types of System Dynamics ModelsManagerial View
of the Enterprise
Strategic
Tactical
2 10 years Horizon
From 25,000
From 10,000
Operations
1 2 years Horizon
Hours/Days/ Weeks/Months
From 1,000
Length of simulation run
To Years
From Days
Jump to Learning in Complex Domains
41Why Business Simulation?
Objectives of business simulations
High
Decision Complexity
Low
High
Development Complexity
42Varieties of business simulations
Different types of business simulators for use at
various levels of the organizational structure.
Value Communication Simulators
C- level
Integrated Decision-Support Simulators
Middle managers
Department Managers
Customers
Suppliers
Line Supervisors Systems Operators
Stakeholders
Training Simulators
43Issues Domain
Issues Domain
Levels of Management Planning Decision-making
High
Strategic (Planning) Long-term
Decision Complexity Risk Magnitude
Tactical (Control) Medium-Term
Operational (Execution) Short-term
Low
44Implementation Process
45The Decision Circle
46Examples of Integrated SolutionsSEM-BPS Dataset
SEM-BPS dataset provides realistic input data to
business simulations
Industry Specific Models
Enterprise Data Warehouse
47Examples of Integrated SolutionsData Manager
Data Manager approach lets users connect to
databases and import/export Powersim variables.
- Simple, custom-built control panel gives
capability to - send database info to Studio at the start of a
time step, - advance the Powersim simulation model, and
- transfer data back from Studio to the database.
- Connects to any SQL/ODBC database (e.g. Oracle).
- Uses a mapping database (implemented with MS
Access) to link database queries/fields to
Powersim variables. - Implemented in Visual Basic.
48Examples of Integrated SolutionsWeb delivery
- The interface is a mix of DHTML and JavaScript
User Interface DHTML/JavaScript
Client
- All communication between client and server is
HTTP
Presentation Tier
HTTP
- Active Server Pages (ASP) is used to control the
server objects - The UI Dependent Objects implement all business
logic for the UI objects - The PS Model objects are used to access Engine.
- The Data Objects are used to ensure object
persistence and for historical and live data. - Powersim Engine runs 1..n instances of a
simulation requested by the PS Model Objects
ASP Interface Server Side VBScript
UI-centric Objects Server installed DLL
Business Tier
Data-centric Objects Server installed DLL
PS Model Objects Server installed DLL
OLE DB/ADO
COM/DCOM
Powersim Engine Server installed OCX and model
file
Enterprise Databases
Representation Tier
Server
49Issues
- Characteristics of Enterprise Challenges
- Dynamic Complexity The Logic of Failure
- System DynamicsMethods and Applications
- Learning in Complex Domains
- Organizational Learning
- Single-loop learning
- Double-loop learning
- Virtual worlds and double-loop learning
50Single-loop Learning
51Double-loop Learning
Reality domain
52Virtual Worlds and Double-loop Learning
Reality domain
Information feedback
Decisions
Mental models
Policy
53Issues
- Characteristics of Enterprise Challenges
- Dynamic Complexity The Logic of Failure
- System DynamicsMethods and Applications
- Learning in Complex Domains
- Organizational Learning
- Fragmentation of Knowledge
- Group Modeling and Knowledge Capture
- Shared knowledge
- Memory of the Future
- Improving Mental Models
54Organizational Learning Fragmented Knowledge
- Can anyone of you make a humble pencil? (In the
sense of setting up a pencil factory from scratch
in a new planet with the same resources the
Earth to be colonized with an expedition on a
spaceship.) - Can anybody on Earth solve that task?
- No! A wonderful essay (I pencil by Leonard E
Read see http//209.217.49.168/vnews.php?nid316
) convincingly shows that no one knows how to
make a pencil. Rather, hundreds of thousands of
different knowledge fragments have to be pulled
together by all kind of mechanisms teamwork,
market mechanisms, demand supply, etc in
order to make a pencil or by that matter any
product. - Knowledge is fragmented. The great economist
Friedrich von Hayek wrote - Economics has long stressed the division of
labour But it has laid much less stress on the
fragmentation of knowledge, on the fact that each
member of society can have only a small fraction
of the knowledge possessed by all, and that each
is therefore ignorant of most of the facts on
which the working of society rests. Yet it is the
utilisation of much more knowledge that anyone
can possess, and therefore the fact that each
moves within a coherent structure most of whose
determinants are unknown to him, that constitutes
the distinctive feature of all advanced
civilisations.
55Organizational Learning Group Modeling and
Knowledge Capture
- Enterprise challenges mostly span across many
fragmented knowledge domains, including knowledge
found outside of the enterprise proper. - Hence, group modeling processes are necessary
- In addition, much is still unknown. Hayek again
- Complete rationality of action demands
complete knowledge of all the relevant facts. A
designer or engineer needs all the data and full
power to control or manipulate them if he is to
organize the material objects to produce the
intended result. But the success of any action in
society depends on more particular facts than
anyone can possibly know. And our whole
civilization in consequence rests, and must rest,
on our believing much that we cannot know to be
true - Implying that data mining, knowledge capturing
processes, including discovey processes are
needed and that a substantial proportion of
assumptions (beliefs) must be made.
56Organizational Learning Shared Knowledge and
Memory of the Future
- The very development of a system dynamic model of
an enterprise challenge leads to shared knowledge
for the client. - System dynamic models should not be used as
predictive tools - rather, they are tools to explore scenarios
(answering what-if questions), thus creating
Memory of the Future (term coined by the Lund
neurologist, professor Dr David Ingvar, 1924,
2000). - The richer such Memory of the Future (e.g. by
identifying robust policies those working under
a wide variety of conditions), the better. - Ultimately, the objective is improving mental
models
57Organizational Learning Improving Mental Models
- Models should not be used as a substitute for
critical thought, but as a tool for improving
judgment and intuition Improving the mental
models upon which decisions are based is the
proper goal of computer modeling. - John D. Sterman A Skeptics Guide to Computer
Models