# Documents about Causal Loop Diagram

• 3 Pages

#### 724Lec05

SUNY Albany, GPR 724

Excerpt: ... ing distance Population in outlying areas Highway construction Average commuting time (B1) Highway expansion Average commuting speed Attractiveness of outlying areas (B3) Commuting volume Net migration to outlying areas Number of commuters Lane-miles of high speed roads PAD 724 lecture notes Page 25 Causal loop diagram s with stocks explicit, but flows implicit in the arrows: Gross productivity Progress rate Fraction satisfactory Workforce Cumulative real progress Undiscovered rework Detection of undiscovered rework Cumulative preceived progress Perceived p roductivity Net hiring Cumulative effort <wcwf> Workforce sought Willingness to change workforce Indicated worforce Effort perceived remaining Tasks perceived remaining Time to detect rework Fraction perceived complete <tdrw> Initial project definition <Workforce sought> Time perceived required Time remaining Indicated completion date Scheduled completion date Net additions to schedule The picture is complete and quantifiable, and may be ...

• 6 Pages

#### ch6sg

Allan Hancock College, WIN 12120

Excerpt: ... sented by differential equations. Terminology Many systems, like those listed in the introduction to this chapter, incorporate feedback -loops, where a change in one part of a system produces changes in the whole system which then "feed back" through the system and affect the original part again. System dynamics refers to the study of such systems. The basic methods of system dynamics were developed by Prof Jay W. Forrester in the late 1950's. Dynamic simulation is a simulation technique that models the levels, flow rates and associated variables of systems that include feedback loops. Causal loop diagram s are a convenient way to represent the loop structure associated with these dynamic systems. Causal Loops Causal loop diagram s are a convenient way to map the interacting elements of feedback loops. They also provide a convenient, easily understood way of describing dynamic systems. Figure 6.1 is a causal loop diagram depicting a room heater control loop. + Room temperature Heat output Gas flow + Figu ...

• 6 Pages

#### ch6sg

Allan Hancock College, COIT 12120

Excerpt: ... ges can be represented by differential equations. Terminology Many systems, like those listed in the introduction to this chapter, incorporate feedback -loops, where a change in one part of a system produces changes in the whole system which then "feed back" through the system and affect the original part again. System dynamics refers to the study of such systems. The basic methods of system dynamics were developed by Prof Jay W. Forrester in the late 1950s. Dynamic simulation is a simulation technique that models the levels, flow rates and associated variables of systems that include feedback loops. Causal loop diagram s are a convenient way to represent the loop structure associated with these dynamic systems. Causal Loops Causal loop diagram s are a convenient way to map the interacting elements of feedback loops. They also provide a convenient, easily understood way of describing dynamic systems. Figure 6.1 is a causal loop diagram depicting a room heater control loop. + Room temperature Heat outpu ...

• 15 Pages

#### PS1

Excerpt: ... CMPT 470 PROBLEM SET 1 FALL 2006 PROBLEM 1: CREATE A CAUSAL LOOP DIAGRAM . In this problem, you will create a causal loop diagram for dynamic behavior associated with some situation you have encountered in your life or with which you are familiar.1 The diagram must include at least 5 factors (labels serving as nodes in the directed graph), and there must be at least 3 different possible paths from start to finish. You are not required to be absolutely sure about the real-world causal relationships to model such a situation with a causal loop diagram ; you can create a causal loop diagram as a working hypothesis for the pattern behind a situation, even if you dont know (or cant recall) all of the detailed mechanisms. Greater credit will be awarded for causal loop diagram s that exhibit greater initiative, clarity of thought, and creativity in conceptualization. While you will be handing in only one diagram for this problem, it is suggested that you follow the following procedure: a) Think about what caus ...

• 3 Pages

#### 624Lec12

SUNY Albany, GPR 624

Excerpt: ... Lecture 12 Page 1 Lecture 12 - Approaches to Conceptualization I. FishBanks model drafts A. Questions? B. Areas to note 1. Fish Net Growth a) Note that Meadows handouts give a rate vs level graph for Fish Net Growth. b) Can use that function as Fis ...

• 40 Pages

#### causalloops

UMass (Amherst), PLNT 597

Excerpt: ... Getting Started With Causal Loop Diagram s or. why did the chicken cross the road? Here is a simple one. actions Mental models Here is another, slightly more complex Sustainable Action Sustainable Pattern Sustainable Mental Models Sustainable Structures This is a reinforcing feedback loop Sustainable Action Sustainable Pattern R Sustainable Mental Models Sustainable Structures Reinforcing loops have an even number of s S S Sustainable Action Sustainable Pattern R Sustainable Mental Models S Sustainable Structures S Lets create a causal loop diagram from The Iceberg Events Patterns of Behavior Systemic Structure Mental Models Increasing Leverage The Iceberg A Sustainable Behavior Events Patterns of Behavior Systemic Structure Mental Models Increasing I rode my bicycle to school today Leverage A pattern The Iceberg Events Patterns of Behavior Systemic Structure Mental Models Increasing Leverage I ride my bicycle to school most days (well, when its not raining) Possi ...

• 14 Pages

#### DynSysIntro

Arkansas Fort Smith, EGR 301

Excerpt: ... Dynamic Systems, Neural Networks Picker Engineering Program Smith College EGR 301 January 25, 2005 Judith Cardell Overview Course administration The purpose of modeling & simulation What is a dynamic system? Policy: Aid to developing countries Engineering: Electric power system How are neural networks and dynamic systems studies related? Pendulum man Modeling and Simulation Systems Experiment with actual system Experiment with a model of a system Mathematical model Physical model Analytic Solution Computer Simulation Systems to Model & Simulate Dynamic system System A combination of interacting elements .that act together to perform a specific objective Dynamic Systems or phenomena that produce time-changing patterns . that evolve or change with time Policy analysis Engineering analysis Policy: Causal Loop Diagram A method for diagramming and understanding relationships between system elements, especially feedback Positive feedback shown below Policy: Causal ...

• 8 Pages

#### ch7sg

Allan Hancock College, WIN 12120

Excerpt: ... n Figure 7.5. There is no equivalent icon in Powersim but the Powersim Flow icons introduce the clouds when the flows are first added to the model. Cloud Symbol Figure 7.5 Flow Diagrams - Clouds Some examples of Flow Diagrams Example 1. Population Growth Consider a very simple model of population growth. In this example, the population of an area is now 100,000 and is growing at the net rate of 2% per year. The model is required to predict the population of the area into the future. Figure 7.6 is the causal loop diagram for this example. Note that the system being modelled is a positive feedback system, because any increase in population will result in an increase in the rate of growth and this in turn reinforces the growth in population. + Population Figure 7.6 Causal Loop for Population Growth Population Growth + For this model, one level is needed for the population of the area. The growth in population can be represented as flow -with-rate where the rate of flow is calculated as 2% of the populati ...

• 8 Pages

#### ch7sg

Allan Hancock College, COIT 12120

Excerpt: ... There is no equivalent icon in Powersim but the Powersim Flow icons introduce the clouds when the flows are first added to the model. Cloud Symbol Figure 7.5 Flow Diagrams - Clouds Some examples of Flow Diagrams Example 1. Population Growth Consider a very simple model of population growth. In this example, the population of an area is now 100,000 and is growing at the net rate of 2% per year. The model is required to predict the population of the area into the future. Figure 7.6 is the causal loop diagram for this example. Note that the system being modelled is a positive feedback system, because any increase in population will result in an increase in the rate of growth and this in turn reinforces the growth in population. + Population Figure 7.6 Causal Loop for Population Growth Population Growth + For this model, one level is needed for the population of the area. The growth in population can be represented as flow -with-rate where the rate of flow is calculated as 2% of the population level. The ...

• 14 Pages

#### w6lect1

Allan Hancock College, WIN 12120

Excerpt: ... System Simulation / Engineering Statistics Winter, 2000 Week 6, Lecture 1. 6-1 Arthur Pinkney, CQU 2001 Flow Diagrams q q q q Causal loop diagram s help identify and organize the principal components and feed back loops but do not contain all of the necessary information Flow diagrams contain more of this necessary information and are an aid to building a dynamic simulation model Indeed, in Powersim and other dynamic simulation packages, the model is built directly from the flow diagram This lecture shows how some systems may be modelled using Powersim 6-2 Arthur Pinkney, CQU 2001 Building Blocks for Flow Diagrams . 1 q Levels. A variable to represent the accumulations in the system. Analogous to the level of liquid in a tank. The level will vary with the in- and out- flows. Examples: Stocks, cash balances, number of people employed Symbol Powersim button 6-3 Arthur Pinkney, CQU 2001 Building Blocks for Flow Diagrams . 2 q Auxiliary variables. These are used when some calculations ...

• 42 Pages

#### l16diagnsprjctrl

MIT, PM 1040

Excerpt: ... Problem Diagnosis & Introduction to Project Dynamics 1.040/1.401J Nathaniel Osgood 4/13/2004 Topics Problem Diagnosis Pareto Analysis Fishbone Diagram Scatterplots Systems Thinking and System Dynamics Causal Loop Diagram s System Dynamics Insights into Causes of Problems Discussed Last Time : Exploratory Analysis Pareto Analysis Fishbone Diagram Scatter Diagram Causal Loop Diagram Pareto Analysis Correctly addressing a small portion of project components can provide control over the remaining project components. Help identify the contributors to given types of performance, mostly cost and quality performance. Group A: a small portion of the major cost components that account for a significant portion of the total cost Group B: all cost component other than Group A and C components Group C: a large portion of the minor cost components that account for a trivial portion of the total cost Pareto Analysis Example: Drivers of Quality Problems in Building Construction Workers Rebar workers Concret ...

• 1 Pages

#### PostelDiscussion

Excerpt: ... Postel Paper Discussion Questions 1. What is accessible runoff (AR) and how is it measured? How do dams increase the amount of accessible runoff? 2. What is the main point of the paper? 3. Why do the authors focus on ET? 4. What is AR and how is it calculated? Is building dams the best option for appropriating AR? 5. How would your analysis of the human appropriation of water be changed if desalinization accounted for 10% of total water appropriation? 6. How would an increase in human population from 5.8 billion (when the paper was written) to 9 billion affect the analysis in this paper? 7. What justice issues should be considered relative to freshwater supply? 8. Based on the factors discussed in the paper, is freshwater a sustainable resource? 9. Are any factors missing from the calculation of AR? Which ones? How might you account for these or measure these factors? 10. Draw a causal loop diagram to express the main relations in the human use of freshwater that are discussed in the paper. 11. What socioecon ...

• 17 Pages

#### Sustaining growth in the modern enterprise

MIT, THSJR 711

Excerpt: ... This structure may be empirically or theoretically discovered and described. Through the discovery of the systems underlying structure, the causal relationships become clear, and predictions may be made of the future behavior of the different agents in the system. The creation of a formal dynamic model of a system requires the identication of the causal relationships that form the systems feedback loops (Forrester, 1971; Sterman, 2000). Generally, feedback loops are thought to be either negative or positive. A negative feedback loop is a series of causal relationships that tend to move behavior towards a goal. In contrast, a positive feedback loop is self-reinforcing. It amplies disturbances in the system to create high variations in behavior. Causal loop diagram s are important tools for representing the feedback structure of the systems. A causal loop diagram consists of variables connected by arrows denoting the causal 276 L. Rabelo, T. Hughes Speller Jr. / J. Eng. Technol. Manage. 22 (2005) ...

• 28 Pages

#### Systems

Penn State, CJN 6

Excerpt: ... ture influences behavior "Different people in the same structure tend to produce the same results. When there are problems it is easy to find someone or something to blame. But, more often than we realize, systems cause their own crises, not external factors or individuals' mistakes." Structure in human systems is subtle "We usually don't see the structures at play much at all. We just find ourselves feeling compelled to act in certain ways." cause and effect not closely related in time and space small changes producing big results from the systems perspective, the human actor is part of a feedback process. We are continually both influenced by and influencing our reality Leverage often comes from new ways of thinking Reject linear cause-and-effect thinking Reject who-is-to-blame thinking Note hidden balancing processes Note hidden processes that reinforce themselves Causal loop diagram s Rather than thinking in terms of linear causal relationships, think of circular causal relationships. From. To. ...

• 8 Pages

#### SD BD Day 1 2 Course Overview Fall 2008

UVA, GBUS 8430

Excerpt: ... Systems Design and Business Dynamics Course Overview Focus: Why business dynamics? Starting Point: What is a system? Thinking and Analysis: What is the nature of a structural hypothesis? End Point: Why design? Systems Design and Business Dynamics: Why should you be here? You will gain a basic understanding and working knowledge of systems thinking fundamentals: performance patterns thinking, archetype stories, causal loop diagram ming and stockflow mapping, pinpointing leverage points. You will gain an appreciation and insight into putting systems thinking into personal and organizational action to design improved system performance. Bottom line: You will be better prepared to contribute to your future organization's ability to see into complexity and offer Few MBAs have this elective content available meaningful facilitation and conversational skills to help others understand systems structure effective systems redesign policies Systems Design and Business Dynamics: Studyin ...

• 3 Pages

#### 724Ex04

SUNY Albany, GPR 724

Excerpt: ... PAD 724- Exercise 4 Diagraming As an interim report on your project model, and an exercise in various diagramming techniques, create the following kinds of diagrams for your project model as you currently envision it. a) Sector overview diagram (sh ...

• 1 Pages

#### Lecture9-10

UCSC, CMPS 080

Excerpt: ... Causal Loop Diagram ming Positive Arc + Negative Arc - Balancing Loop odd minuses Reinforcing Loop Even Minuses Deterministic = No element of chance The same state always leads to the same future, given the same input. Non-deterministic = Not deterministic = Stochastic = Chance Mathematical functions are deterministic they are many to or 1-1. Random = "All states equally likely" = maximum diversity = log2(N) the number states. is a special case of stochastic. (actually very difficult to create or prove a random system - so the term ultimately refers to "maximal ignorance"). SUBJECTIVE VIEW: [ which instructor recommends] Probabilities are due to our ignorance and are not part of the world. information/energy chart: dynamic T = maximum diversity = random hot free = log2(N) . . . . . . . . static ...

• 51 Pages

#### L4_Lifecycle_Documentation

Old Dominion, COMP 3705

Excerpt: ... ivation Advanced Software Engineering 42 Model No model is perfect, but some models are useful Dynamic behaviour Model scope System behaviour can change over time Dynamic, discrete-event, etc. Behaviour and decisions made at one point in the process impact others in complex or indirect ways A portion of the life cycle A development project Multiple, concurrent projects Amount of incoming work Defect detection efficiency Effort for code rework Effort/cost Cycle-time etc Feedback mechanisms Input parameters Result variables Advanced Software Engineering 43 Quality factors Advanced Software Engineering 44 Influence diagram Time in Requirement Phase Inadequate Requirements Amount of rework Specification Accuracy Amount of Review Number of Personnel Schedule Pressure Budget Pressure Amount of New Market Requirements Communication Level Personnel Experience Functionality Productivity Advanced Software Engineering 45 Causal loop diagram - ...

• 5 Pages

#### Lab7a

Washington, QSCI 110

Excerpt: ... 16.13. Once you have done that, keep pressing PLAY until the simulation has run up through 1940. Problem 3: a) Turn in a copy of this graph. b) Explain why the net birth rate declines as the number of predators decreases. You may need to play with the simulation a little to understand this. Problem 4: Draw the causal loop diagram of this model. No simulation required. As a reminder, our reference mode is an overshoot condition and collapse condition, similar to that shown in Fig 16.1 of the text. When you simulate the model, however, you will see that the collapse condition does not occur. While there is a decrease in the deer population, as evidenced by the negative net birth rate, the decrease is small and so the population declines only gradually. So, our model structure is probably not quite right yet. Ford (p193) makes the point that even with running the model under some different parameterizations, the predicted overshoot of the reference mode cannot be adequately represented. One questionable assumpt ...

• 5 Pages

#### SAE 599 Fall 2007 - Modeling and Simulation for...

USC, SAE 599

Excerpt: ... SAE 599 - Modeling and Simulation for Systems Architecting and Engineering Dr. Raymond Madachy October 24, 2007 Modeling Communication and Team Issues (from reading assignment) Communication is vitally important in modeling Seek early involvement from stakeholders or modeling efforts arent likely to succeed Developing buy-in to the model is usually more important than the model itself. Otherwise the results will never be used. Everyone comes with pre-conceived mental models and success criteria. Open communication will help elucidate those models and identify clashes. Be aware of the different perspectives and skillsets of your audience Use simple diagrams to communicate with others until they seek more detail Causal loop diagram s are sometimes better to describe a model than a fully elaborated, executable version. They can get the important points across. Try to facilitate interaction with the model. Use a control panel interface and pictures. Documentati ...

• 1 Pages