Types of Agent

We are having four types of agents

• Simple Reflex agent(Condition-action rule)
• Model Based Reflex agent(State Based)
• Goal Based agent(Goal)
• Utility Based agent(Priority)

Simple Reflex agent 

 The decision(Action) can be chosen based on current perception of the world not the past one.In other words we can say If perceives then act(Condition-action rule).

Consider a Mars Lander as an example,it collects rocks once it sense and it will not bother about the past perception. Assume it collects a rock,again it senses the rock it collects without knowing that this type of rock is already collected or not.This is we represent as Simple Reflex Agent.

Condition action rule--->if rock then collect

Model Based Reflex agent

 In this type of agent,there is an an internal state which maintains important information from previous percepts.This internal state helps an agent to do action.

Again consider a Mars Lander,it sense the rocks and checking for previous state before perform collection action ,whether this type of rock is already collected or not.

Condition action rule--->if rock check for previous state then collect

Goal Based Agent

This type of agent tries to reach a desirable state,The Goal.
  

Utility Based agent 
 A utility function maps each state after each action to a real number representing how efficiently each action achieves the goal. This is useful when we either have many actions all solving the same goal or when we have many goals that can be satisfied and we need to choose an action to perform.
 

Consider the  mars Lander on the surface of mars with an obstacle in its way. In a goal based agent it is uncertain which path will be taken by the agent and some a re clearly not as efficient as others but in a utility based agent the best path will have the best output from the utility function and that path will be chosen.