# Shared Flashcard Set

## Details

An introduction to Modeling
Empiracal Methods
26
International Studies
09/13/2011

Term
 what are models
Definition
 simplified representations of some reality
Term
 what is the most sophisticated type of model? characteristics
Definition
 computational model:A computational model attempts to emulate some aspect or subset of the worldA computational model attempts to correctly represent the progression through time of that subset of the world
Term
 name the most basic kind of model
Definition
 mental models
Term
 An Example Mental Model
Definition
 If I witness the emergence of a problem, a growing gap between what I would like and what is happening, I expect that the problem will continue to grow at the same trajectory unless something else intervenesA mental model operates with a relatively simple rule-set, statements about what to do in different situations
Term
 What is a gap?
Definition
 difference between what I would like to see happening in a particular arena and what is actually happeningGap = Desired value of variable - Actual value of variable
Term
 rule of thumb regarding gaps
Definition
 If the difference between what is desired and what is happening in a numerical measure that captures change in the arena exceeds 20% of the absolute value of that variable, there is a gapElse, there is no gap because the difference is (relatively) too small to have a significant impact
Term
 a rule-set regarding gaps changing for mental models
Definition
 If Gap is changing, the amount the gap will get larger or smaller will be the same as the degree of change between the last time I looked and now
Term
 next to the most basic kind of model?
Definition
 articulated models is a subset of mental models. nickname:coherent description
Term
 Articulated Models
Definition
 Articulated models are those mental models expressed to others, a small subsetArticulated models are descriptions of how things relate to each otherArticulation imposes some degree of coherenceArticulated models can be comparedSuperior articulated models can be identified
Term
 gap changes over time
Definition
 In a situation where the amount of change depends on the starting point, an exponential growth model is superior to a linear growth model
Term
 An Alternative Mental Model process
Definition
 Monitor a variety of indicators that reach at or measure fundamental processesFor those indicators where a consistent gap emerges, try determine whether a process that causes the gap is an exponential growth processIf yes, expect that the problem will get increasingly worse in an accelerating manner unless something is done to offset the effect of that processElse, use decision-rule of the original mental modelAn articulated model shown to be superior should be able to be incorporated into a mental model
Term
 An Alternative Mental Model process
Definition
 Monitor a variety of indicators that reach at or measure fundamental processesFor those indicators where a consistent gap emerges, try determine whether a process that causes the gap is an exponential growth processIf yes, expect that the problem will get increasingly worse in an accelerating manner unless something is done to offset the effect of that processElse, use decision-rule of the original mental modelAn articulated model shown to be superior should be able to be incorporated into a mental model
Term
 third model kind
Definition
 formal model, subset of articulated, which is a subset of mental.
Term
 Formal Models
Definition
 Formal models are, in turn, a small subset of articulated modelsFormal models are those articulated models expressed using a language that imposes strong logical rigor such as algebra, differential calculus, or predicate calculus in mathematicsMany different types of formal models have been developed
Term
 Computational Models
Definition
 Computational models are that subset of formal models put into a form that can be represented in a computer algorithmThrough the running of the algorithm, a series of steps, a computational model can simulate “stepping” through time by the object or process described by the formal modelComputational models can be and often are aggregations of formal models
Term
 What is the hierarchy of systems?
Definition
 Simple systemsStepped systemsGoal-seeking systemsAdaptive systemsPurposive systems
Term
 Example of a simple system?
Definition
 wages, unemployment, and inflation affect economic Well Being
Term
 Simple Systems
Definition
 Simple systems are a limited number of objects connected in simple waysSimple models of social processes encompass the set of factors that make something changeA simple model consists of a thing that changes because of a change in something else (one example being a dependent variable) with that something else being some set of explanatory factors (or causal variables)
Term
 Example of a Stepped System
Definition
 labor legislation affects wages and so does GDP. GDP affects unemployment. Wages and unemployment affect Economic WB
Term
 Stepped Systems
Definition
 Stepped systems incorporate chains of causationA thing that changes the dependent variable is in turn dependent upon something elseRecursive simultaneous equations models represent stepped systems
Term
 examle of a goal-seeking system
Definition
 same as step but now from economic WB, goes to reality goals gap and a separate thing that creates the gap is the actual goals which the gap affects decision making which affects a different part of the system like teh GDP.
Term
 Goal-seeking Systems
Definition
 Goal-seeking systems attempt to reach some desired end-state, usually an equilibriumThe chain of causation includes at least one feedback loop, a linkage from some point in the chain back to an earlier point in the chainA goal-seeking system needs at least one negative feedback loop, feedback that creates a tendency to go in one direction, a desired end-stateAdam Smith’s “Invisible Hand” is a set of negative feedback loops that work to stabilize an economy
Term
Definition
 same as goal-seeking but when the decisions dont really change the reality goals gap they change the decision making mechanism
Term