Artificial Intelligence - Chapter 2 Agents and Rational Agents Part II

Artificial Intelligence - Chapter 2

Agents and Rational Agents

Part II

The range of task environments that might arise in AI is obviously vast. We can, however, identify a fairly small number of dimensions along which task environments can be categorized. These dimensions determine, to a large extent, the appropriate agent design and the applicability of each of the principal families of techniques for agent implementation.

T HE S TRUCTURE OF A GENTS

So far we have talked about agents by describing behavior—the action that is performed after any given sequence of percepts. Now we must bite the bullet and talk about how the insides work. The job of AI is to design an agent program that implements the agent function—the mapping from percepts to actions. We assume this program will run on some sort of computing device with physical sensors and actuators—we call this the architecture:
                   agent = architecture + program .

In the remainder of this section, we outline four basic kinds of agent programs that embody the principles underlying almost all intelligent systems:
    •Simple reflex agents;
    •Model-based reflex agents;
    •Goal-based agents; and
    •Utility-based agents.
Each kind of agent program combines particular components in particular ways to generate actions.

The simplest kind of agent is the simple reflex agent. These agents select actions on the basis of the current percept, ignoring the rest of the percept history.

The most effective way to handle partial observability is for the agent to keep track of the part of the world it can’t see now. That is, the agent should maintain some sort of internal state that depends on the percept history and thereby reflects at least some of the unobserved aspects of the current state.

Contents of Lecture

Properties of Task Environment
Software Agents - SoftBots
How is an Agent different from other software?
Environment Types
Structure of Intelligent Agents
Agent types
•Reflex agents
•Reflex agents with internal states
•Goal-based agents
•Utility-based agents

Artificial Intelligence - Chapter 2 Agents and Rational Agents Part II