Chapter 3 Flashcards
“Representation of a system” to be bought into being, or to analyze a system in already inbeing.
Model
Are designed to represent a system under study, by an idealized example of reality, to explain the essential relationship involved.
Models
Models can be classified by distinguishing:
Physical
Analogue
Schematic
Mathematical
Are geometric equivalents, either a miniatures, enlargements, or duplicate made to the same scale.
Physical Models
Ex. Globe
Comes from the Greek word analogia
Analogue Models
Analogia means __
Proportion
Thus model focuses on the similarity in relations
Analogue Models
Example: analogue computers use electronic components to model power distribution systems, chemical processes, and dynamic loading structures.
It is represented by symbols in the computer program and not by the physical structure of the computer components.
Analogue Models
It is developed by reducing a state or event to a chart or diagram.
Schematic Models
A common schematic model. It is a representation of the state of formal relationship existing between various members of the organization
Organization chart
A schematic model that describe the order or occurrence of several events that constitute an object, such as the assembly of an automobile from a multitude of components parts
Flow process chart
It employ the language of mathematics and, like other models, may be a description an then an explanation of the system it represents.
Mathematical Models
Although its symbols may be more difficult to comprehend than verbal symbols, they do provide a much higher degree of abstraction and precision in their application.
Mathematical Models
Ex. Boyle’s law, ohm’s law, and newton’s laws of motion
Is an important part of the systems engineering and analysis
Decision evaluation
Is needed as a basis for choosing among the alternatives that arise during the activities of system design, as well as for optimizing system already in operation.
Evaluation
A course of action or strategy that may be chosen by the decision maker.
Alternative
An occurrence or a situation over which the decision maker has little or no control.
State of Nature
The benefit which occurs from a given combination of decision alternative and state of nature.
Payoff
Is designed for situations which ideas, feelings, and emotions affecting the decision process are quantified to provide a numeric scale for prioritizing the alternatives.
AHP (Analytic Hierarchy Process)
_______the payoffs associated with each decision alternative are describe by probability distribution. For this reason, decision making ______ can be based on the expected value criterion, which decision alternatives are compared based on the maximization of expected profit or the minimization of the expected cost.
Under conditions of risk
Under risk
The expected value criterion seeks the maximization of expected (average) profit or the minimization of expected cost. The data of the problem assumes that the payoff (or cost) associated with each decision alternative is probabilistic.
Decision Tree-Based expected value criterion
Considers simple decision situations with a finite number of decision alternatives and explicit payoff matrices.
Decision Tree Analysis
Issues relating to the expected value criterion. The first issue deals with ________ and second is _____
-Determination of posterior probabilities based in experimentation
-utility versus the actual value of money
The probabilities used in the expected value criterion are usually determined from historical data. In some cases, these probabilities can be adjusted using additional information based on ____ or _____. The resulting probabilities are refered to as ________, as opposed to the prior probabilities determined from raw data.
Sampling, experimentation
Posterior (Baye’s) probabilities
