Lecture EIGHT.

What is the purpose of Heuristic Function?

• To select the most promising path for expansion

• To keep all nodes in memory

• To ignore the path cost entirely

• To estimate the cost of reaching the goal from a node

What does a heuristic function do in informed search?

• It takes the current state of the agent as input and produces the estimation of how close the agent is from the goal

• It measures the cheapest total estimated cost from the initial state to the goal state through the current state

• It estimates the true cost to reach a goal state from a node

• It orders the nodes to be expanded based on the sum of backward cost and goal proximity

The heuristic function, always give the best solution.

• False

• True

Answer explanation

The heuristic function, might not always give the best solution, but it guaranteed to find a good solution in responsible time.

What's the aim for a heuristic function h(n) ?

• Estimate the cost of the most expensive path from the current state to the goal state

• Randomly select the next state

• Count the number of nodes in the graph

• Estimate the cost of the cheapest path from the current state to the goal state

What is the strategy of the greedy best-first search algorithm?

• Expand the node with the lowest total estimated cost

• Expand the node with the lowest path cost

• Expand the node that seems closest to the goal

• Expand the node with the highest goal proximity

What's the simplest and straightforward approach in search algorithms?

• A* search

• Greedy best-first search

• AO* search

• UCS

______ is likely to be complement of uniform cost search.

• A* search

• Greedy best-first search

• AO* search

• UCS

What is the activation function used in Greedy best-first search algorithm?

• f(n) = g(n)

• f(n) = g(n) + h(n)

• f(n) = g(n) - h(n)

• f(n) = h(n)

What're the properties of Greedy best-first ?

• complete.
  NOT optimal.

• complete.

  optimal.

• NOT complete.

  optimal.

• NOT complete.

  NOT optimal.

Why A* was proposed in 1968?

• To slow down the progress of search algorithms

• To make the search process less efficient

• To make the search process more complicated

• to improve robots to navigate through a room with obstacles.