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Questions and Answers

What is the primary difference between informed search and uninformed search algorithms?

Informed search is used for goal-based agents, while uninformed search is used for problem-solving agents.

Informed search is faster, while uninformed search is more accurate.

Informed search uses a transition model, while uninformed search does not.

Informed search has additional information to judge the promise of an action, while uninformed search does not. (correct)

What is the search strategy defined by?

The method used to traverse the search tree.

The method used to formulate the search problem.

The method used to evaluate the goal test.

The method used to choose the next node from available actions. (correct)

What is the primary purpose of the transition model in a search problem formulation?

To determine the goal state.

To define the available actions. (correct)

To provide additional information for informed search.

To evaluate the step/path cost.

What type of agent is most likely to use a search algorithm?

Goal-based agent. Signup and view all the answers

What is the purpose of the goal test in a search problem formulation?

To determine if the goal state has been reached. Signup and view all the answers

What is the primary advantage of using an informed search algorithm over an uninformed search algorithm?

Informed search algorithms can take advantage of additional information to guide the search. Signup and view all the answers

What is the primary goal of a goal-based agent?

To reach a goal state from an initial state Signup and view all the answers

What is the term for the process of looking for a sequence of actions to reach a goal?

Search Signup and view all the answers

What is the requirement for defining a search problem?

Defining the initial state, actions, transition model, and goal state Signup and view all the answers

What is the characteristic of a search problem environment?

Fully observable and deterministic Signup and view all the answers

What is the term for the function that describes the possible actions available at each state?

Successor function Signup and view all the answers

What is the purpose of a transition model in a search problem?

To describe what each action does Signup and view all the answers

What is an optimal solution in a search problem?

A solution that has the least cost among all solutions Signup and view all the answers

What is the primary assumption of a goal-based agent?

The environment is fully observable and deterministic Signup and view all the answers

What is the primary difference between a state space graph and a search tree?

The representation of nodes as paths in the state space Signup and view all the answers

What is the main advantage of constructing the search tree on demand?

It reduces the memory required to store the tree Signup and view all the answers

In a search tree, what does each node represent?

A path in the state space graph Signup and view all the answers

What is the purpose of checking for repeated states in a search algorithm?

To avoid infinite loops in the search Signup and view all the answers

What is the main difference between a general tree search and a goal-based search?

The criteria for selecting the next node to expand Signup and view all the answers

What is the benefit of using a data structure to store the frontier nodes in a search algorithm?

It allows for more efficient exploration of the state space Signup and view all the answers

What is the purpose of a search strategy in a goal-based search?

To select the next node to expand based on the goal state Signup and view all the answers

What is the main advantage of using a search tree instead of a state space graph?

It enables the search algorithm to focus on the goal state Signup and view all the answers

Study Notes

Search Algorithms

Types of search algorithms: Uninformed Search and Informed Search
Uninformed Search: only has information provided by problem formulation (initial state, available actions, transition model, goal test, and step/path cost)
Informed Search: has additional information to judge promise of an action, i.e. estimated cost from a state to a goal

Agents

Key differences between agents: capabilities, decision-making processes, handling of uncertainty, and adaptability to environments and tasks
Simple reflex agents: most basic, goal-based agents: intermediate in complexity, and learning agents: adaptive and capable of improving performance through experience

Goal-Based Agent

Also called a problem-solving agent or planning agent
Performs actions to get from initial state to a goal
Process of looking for a sequence of actions to reach a goal is called search
Requirements of searching:
- Define problem
- Represent search space by states
- Define actions the agent can perform
- Define costs associated with actions
- Define a goal: what is the agent searching for?
- Define a solution: an action sequence that reaches a goal state
- An optimal solution has the least cost among all solutions

Search Problem Formulation

A search problem consists of five components:
- Initial state (S0) that the agent starts in
- Possible actions available at each state (Successor Function)
- Transition model describing what each action does
- Goal test
- Path cost function

State Space Graphs and Search Trees

State Space Graph: represents all possible states and transitions
Search Tree: a partial representation of the state space graph, constructed on demand
Main variations of tree search:
- Which leaf node to expand next
- Whether to check for repeated states
- Data structures for frontier, expanded nodes

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