Midterm 1 Flashcards
What is an AGENT?
Anything that can be viewed as perceiving through its ENVIRONMENT through SENSORS and ACTING upon that environment through ACTUATORS.
What is a PERCEPT SEQUENCE?
The complete history of everything the agent has perceived.
What is the role of an AGENT FUNCTION?
To map any given percept to an action.
What is the difference between an agent FUNCTION and an agent PROGRAM?
FUNCTION: Mathematical abstraction. PROGRAM: Concrete implementation, running within some physical system.
What are the components of the TASK ENVIRONMENT?
Performance measure: desirable qualities Environment Actuators: methods of control over device/vehicle Sensors: sensory input
Describe a SIMPLE REFLEX AGENT.
An agent whose action depends only on the current percept.
Describe a MODEL-BASED AGENT.
An agent whose action is derived directly from an internal model of the current world sate that is updated over time.
Describe a GOAL-BASED AGENT.
An agent that selects actions that it believes will achieve explicitly represented goals.
Describe a UTILITY-BASED AGENT.
An agent that selects actions that it beileves will maximize the expected utility of the outcome state.
Describe the components of a LEARNING AGENT.
An agent whose bhavior improves over time based on its experience.
LEARNING ELEMENT: responsible for making improvements
PERFORMANCE ELEMENT: responsible for selecting external actions
CRITIC: provides feedback to agent and determines how performance element should be modified to do better in the future
PROBLEM GENERATOR: responsible for suggesting actions that will lead to new and informative experiences
What are the FIVE components of a PROBLEM?
- Initial State
- Actions
- Transition Model
- Goal Test
- Path Cost
Define STATE SPACE.
State space is defined by initial state, actions, and transition model. It is the set of all states reachable from the initial state by any sequence of actions.
Define FRINGE/FRONTIER.
The set of nodes available for expansion.
Properties of Breadth-First Search:
- Complete?
- Time?
- Space?
- Optimal?
Complete: Yes
Time: O(b^d)
Space? O(b^d)
Optimal? Yes, not optimal in general
Properties of Uniform-Cost Search:
- Complete?
- Time?
- Space?
- Optimal?
Expand least-cost unexpanded node.
- Complete: Yes, for step > e where e = some small, positive constant
- Time: O(b ^ C* / e)
- Space: O(b ^ C* / e), which can be wose than b^d
- Optimal: Yes