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To be good enough for the real world although not perfect.

But then,
it's not a perfect world.

Go to the Overview of the Design Process


A Definition of Satisfice

"To accept a choice or judgment as one that is good enough, one that satisfies. According to Herb Simon, who coined the term, the tendency to satisfice shows up in many cognitive tasks such as playing games, solving problems, and making financial decisions where people typically do not or cannot search for the optimal solutions."


Source: The Penguin Dictionary of Psychology, © Arthur S. Reber 1995.

A Second Definition of Satisfice

"To obtain an outcome that is good enough. Satisficing action can be contrasted with maximizing action, which seeks the biggest, or with optimizing action, which seeks the best.

"In recent decades doubts have arisen about the view that in all rational decision-making the agent seeks the best result. Instead, it is argued, it is often rational to seek to satisfice i.e. to get a good result that is good enough although not necessarily the best."

Source: http://www.utilitarianism.com/satisfice.htm

The Process

"Satisficing" means deciding what constitutes a satisfactory outcome and then looking for ways to achieve it. We stop looking when when we have "satsficed."

Most often, we look for what's worked for us before. The difficulty here is that there may be even better ways to reach the outcome. Satisficing is not, therefore, choosing the first thing that might work.

However, looking for better ways carries a cost, and a better solution would have to justify the extra costs of finding it. On the other hand, not looking hard enough carries a cost if the project fails to win support from users or sponsors.

The decision maker, therefore, has a choice between optimal decisions for an imaginary simplified world or decisions that are "good enough," that satisfice, for a world approximating the complex real one more closely. It's an ongoing empirical process of searching, implementing, and testing.

A Operational Test of Satisfice for PW408

  • Was learning effective (as defined by the objectives)?
  • Was learning efficient (were there wasted steps, false starts, distractions, etc.)?

Some quotes from Herbert Simon

from "The Sciences of the Artificial", 2nd ed. by Herbert Simon.
Published by The MIT Press, Cambridge, MA, 1981.

Design

Engineering, medicine, business, architecture and painting are concerned not with the necessary but with the contingent - not with how things are but with how they might be - in short, with design.

How Things
Ought To Be

The engineer, and more generally the designer, is concerned with how things ought to be - how they ought to be in order to attain goals, and to function …

Evolution

The simplest scheme of evolution is one that depends on two processes; a generator and a test. The task of the generator is to produce variety, new forms that have not existed previously, whereas the task of the test is to cull out the newly generated forms so that only those that are well fitted to the environment will survive.

Internal Limitations

What a person cannot do he will not do, no matter how much he wants to do it. Normative economics has shown that exact solutions to the larger optimization problems of the real world are simply not within reach or sight. … the behavior of an artificial system may be strongly influenced by the limits of its adaptive capacities.

Adaptation

… to use feedback to correct for unexpected or incorrectly predicted events. Even if the anticipation of events is imperfect and the response to them less than accurate, adaptive systems may remain stable in the face of sizable jolts …

Hierarchy and the Functional Paradigm

To design … a complex structure, one powerful technique is to discover viable ways of decomposing it into semi-independent components corresponding to its many functional parts. The design of each component can then be carried out with some degree of independence of the design of others, since each will affect the others largely through its function and independently of the details of the mechanisms that accomplish the function.

Taxonomy of Representation

An early step toward understanding any set of phenomena is to learn what kinds of things there are in the set - to develop a taxonomy.

Complexity as Hierarchy

… complexity frequently takes the form of hierarchy and that hierarchic systems have some common properties independent of their specific content. Hierarchy … is one of the central structural schemes that the architect of complexity uses.

Description of Complex Systems

… two main types of description … (for) understanding of complex systems … (are) state description and process description. The former characterizes the world as senses; they provide the criteria for identifying objects, often by modeling the objects themselves. The latter characterize the world as acted upon; they provide the means for producing or generating objects having the desired characteristics.