Questions tagged [heuristics]

In AI, the term "heuristic" is used in the context of non-blind (i.e., informed) search and planning: the problem of finding a sequence of actions to find/generate a desired state from an initial state. Heuristics" are problem relaxations of the original problem. They get as input the current state/search node and output the cost of the relaxed solution from there to goal. This heuristic value is then used for search guidance.

Filter by
Sorted by
Tagged with
2
votes
1answer
52 views

Agents meeting in a directed connected graph

We have a directed connected graph, where nodes are places one can go to and edges are the "roads" between places. We have K agents whose goal is to meet in one node. Agents start in ...
1
vote
1answer
58 views

Determining minimal state representation for maze game

I came across this question set. It asks following question: Let’s revisit our bug friends from assignment 2. To recap, you control one or more insects in a rectangular maze-like environment with ...
13
votes
1answer
14k views

Why is A* optimal if the heuristic function is admissible?

A heuristic is admissible if it never overestimates the true cost to reach the goal node from $n$. If a heuristic is consistent, then the heuristic value of $n$ is never greater than the cost of its ...
0
votes
0answers
15 views

Why is that the heuristic is not admissible, then it is not consistent [duplicate]

I don't understand why if the heuristic is not admissible then it is not consistent?
2
votes
0answers
46 views

Are there heuristics that play Klondike Solitaire well?

Are there heuristics that play Klondike Solitaire well? I know there are some good exhaustive search solvers for Klondike Solitaire. The best one that I know of is Solvitaire (2019) which uses DFS, (...
2
votes
1answer
71 views

Why aren’t heuristics for Connect Four Monte Carlo tree search improving the agent?

I’ve created an agent using MCTS to play Connect Four. It wins against humans pretty well, but I’d like to improve upon it. I decided to add domain knowledge to the MCTS rollout stage. My evaluation ...
0
votes
0answers
29 views

Incorrect node expansion in game board with A* search

I have the following game board below, and we're using A* search to find the optimal path from the agent to the key. There are 8 directions. Up, down, left, right have a cost of 1, and diagonal ...
0
votes
0answers
24 views

Can an inadmissable heuristic be consistent? [duplicate]

If something is inadmissible, can we just assume it's also inconsistent? Also, I understand how to check if a heuristic is inadmissible, but I'm still a bit confused on checking consistency. If I have ...
6
votes
4answers
4k views

What else can boost iterative deepening with alpha-beta pruning?

I read about minimax, then alpha-beta pruning, and then about iterative deepening. Iterative deepening coupled with alpha-beta pruning proves to quite efficient as compared to alpha-beta alone. I have ...
0
votes
0answers
23 views

Satisficing searches - how does speedy search compensate for higher execution costs

While reading AI: A Modern Approach (4th ed), I have some difficulty in coming to terms with the usefulness of a satisficing search. Generally speaking, I understand that in real life situations we ...
7
votes
0answers
83 views

Why is my GAN more unstable with bigger networks?

I am working with generative adversarial networks (GANs) and one of my aims at the moment is to reproduce samples in two dimensions that are distributed according to a circle (see animation). When ...
1
vote
0answers
19 views

CSP heuristic to simultaneously reduce conflicts and find near optimal assignment

I am trying to design a good heuristic to solve a constraint satisfaction problem (CSP). I think that a possible heuristic to use is $$h_1(\text{state}) = \text{number of conflicts in state}$$ However,...
7
votes
1answer
166 views

A* is similar to Dijkstra with reduced cost

According to this Wikipedia article If the heuristic $h$ satisfies the additional condition $h(x) \leq d(x, y) + h(y)$ for every edge $(x, y)$ of the graph (where $d$ denotes the length of that edge),...
2
votes
3answers
5k views

What heuristic to use when doing A* search with multiple targets? [closed]

Usually, using the Manhattan distance as a heuristic function is enough when we do an A* search with one target. However, it seems like for multiple goals, this is not the most useful way. Which ...
2
votes
1answer
354 views

Is A* with an admissible but inconsistent heuristic optimal?

I understand that, in tree search, an admissible heuristic implies that $A*$ is optimal. The intuitive way I think about this is as follows: Let $P$ and $Q$ be two costs from any respective nodes $p$ ...
1
vote
1answer
139 views

Which heuristics guarantee the optimality of A*?

The following is a statement and I am trying to figure out if it's true or false and why. Given a non-admissible heuristic function, A* will always give a solution if one exists, but there is no ...
0
votes
1answer
4k views

How do you calculate the heuristic value in this specific case?

The A* algorithm uses the "evaluation function" $f(n) = g(n) + h(n)$, where $g(n)$ = cost of the path from the start node to node $n$ $h(n)$ = estimated cost of the cheapest path from $n$ to the ...
2
votes
3answers
633 views

What is the definition of a heuristic function in the BayesChess paper?

I am reading BayesChess: A computer chess program based on Bayesian networks (Fernandez, Salmeron; 2008) It is a chess-playing engine using Bayesian networks. The following is mentioned about the ...
2
votes
0answers
41 views

How does heuristic work with multiple agents?

I have a question for heuristic search with multiple agents. I know how heuristic search works with one agent (ex. one Pacman) but I don't really understand it with multiple agents. Let's say we have ...
3
votes
1answer
94 views

How to find proper parameter settings for a given optimization algorithm?

Is there any methodology to find proper parameter settings for a given meta-heuristic algorithm, e.g. the firefly algorithm or the cuckoo search? Is this an open issue in optimization? Is extensive ...
3
votes
1answer
363 views

Is the summation of consistent heuristic functions also consistent?

Imagine that we have a set of heuristic functions $\{h_i\}_{i=1}^N$, where each $h_i$ is both admissible and consistent (monotonic). Is $\sum_{i=1}^N h_i$ still consistent or not? Is there any proof ...
2
votes
0answers
286 views

Can the degree and minimum remaining values heuristics be used in conjunction?

I am currently studying constraint satisfaction problems and have come across two heuristics for variable selection. The minimum remaining values(MRV) heuristic and the degree heuristic. The MRV ...
2
votes
1answer
50 views

What are some common heuristics that might be innate?

Here's a question I might ask an AI to solve: "Colour the states of the USA using just 4 colours". Now, a common heuristic a human might use is to start at one ...
7
votes
3answers
664 views

More effective way to improve the heuristics of an AI... evolution or testing between thousands of pre-determined sets of heuristics?

I'm making a Connect Four game where my engine uses Minimax with Alpha-Beta pruning to search. Since Alpha-Beta pruning is much more effective when it looks at the best moves first (since then it can ...
1
vote
1answer
646 views

Why is the effective branching factor used for measuring performance of a heuristic function?

For search algorithms with heuristic functions, performance of heuristic functions are measured by effective branching factor ${b^*}$ which involves total nodes expanded ${N}$ and depth of the ...
3
votes
1answer
1k views

Is the minimum and maximum of a set of admissible and consistent heuristics also consistent and admissible?

Let's suppose I have a set of heuristics $H$ = {$h_1, h_2, ..., h_N$}. If all heuristics in $H$ are admissible, does that mean that a heuristic that takes the $\min(H)$ (or $\max(H)$ for that matter) ...
6
votes
1answer
158 views

Can two admissable heuristics not dominate each other?

I am working on a project for my artificial intelligence class. I was wondering if I have 2 admissible heuristics, A and B, is it possible that A does not dominate B and B does not dominate A? I am ...
6
votes
2answers
876 views

How does A* search work given there are multiple goal states?

When I have read through the fundamentals of AI, I saw a situation (i.e., a search space) which is illustrated in the following picture. These are the heuristic estimates: ...
2
votes
1answer
404 views

Understanding the proof that A* search is optimal

I don't understand the proof that $A^*$ is optimal. The proof is by contradiction: Assume $A^*$ returns $p$ but there exists a $p'$ that is cheaper. When $p$ is chosen from the frontier, assume $...
3
votes
1answer
329 views

How do I find whether this heuristic is or not admissible and consistent?

I was given the following problem to solve. Given a circular trail divided by $n> 2$ segments labeled $0 \dots n-1$. In the beginning, an agent is at the start of segment number $0$ (the edge ...
3
votes
0answers
120 views

How to choose the weights for a linear combination of heuristic functions?

I need to write a minimax algorithm with alpha-beta pruning in limited time for the 2048 game. I know expectimax is better for this work. Assume I wrote different heuristic functions. If I want to ...
11
votes
1answer
188 views

Strategic planning and multi dimensional knapsack problem

I'm trying to find a planning approach to solve a problem that attempts to model learning of new material. We assume that we only have one resource such as Wikipedia, which contains a list of articles ...
3
votes
0answers
54 views

What kind of decision rule algorithm is usable in this situation?

I am trying to write an AI to a game, where there is no real adversary. This means, that only the AI player has choices in which move to perform, his opponent may or may not react to the move the AI ...
12
votes
5answers
889 views

Are methods of exhaustive search considered to be AI?

Some programs do exhaustive searches for a solution while others do heuristic searches for a similar answer. For example, in chess, the search for the best next move tends to be more exhaustive in ...
2
votes
0answers
292 views

Snake path finding variant : Algorithm choice

I am working on a project which maps to a variant of path finding problem. I am new to this area and I would be very grateful if you could give suggestions/ point to libraries for relevant algorithms. ...
1
vote
0answers
21 views

Approach for data transformation needed

I am looking for an algorithm to transform an input data to a goal data using a series of operations. The shorter the series the better. The following is known: the input data the goal data input ...
2
votes
0answers
48 views

How to open up a rigid structure made of connected panels?

By open up I mean slightly open up so that a theoretical structure of panels with no width looks three-dimensional. The original structure being an ideal object where any number several panels can ...
5
votes
1answer
2k views

Blocks world Game: A* heuristic solution approach

I am developing a heuristic solution for blocks world problem. I tried using number of blocks out of place as my h(n). It seems little ineffective. Can someone please point out a suitable heuristic ...
1
vote
0answers
761 views

Has Tic-Tac-Toe been solved with a single heuristic?

By this I mean a single axiom for placement. (I'm working on a solution that involves positional valuation and vectors, and appears to be solid, but my assumption would be this has been done ...
4
votes
1answer
70 views

What are state-of-the-art ways of using greedy heuristics to initially set the weights of a Deep Q-Network in Reinforcement Learning?

I am interested in the current state-of-the-art ways to use quick, greedy heuristics in order to speed up the learning in a Deep Q-Network in Reinforcement Learning. In classical RL, I initially set ...
3
votes
0answers
38 views

Knapsack of mixture with constraints

I'm trying to find the optimized mixture for a specific set of substances. Each of those substances have characteristics that I want to optimize in the mixture (some characteristics I want to minimize ...
3
votes
3answers
76 views

Is a subset of a problem solution, used to recreate complete solution considered a heuristic?

This is a question about a nomenclature - we already have the algorithm/solution, but we're not sure whether it qualifies as utilizing heuristics or not. feel free to skip the problem explanation: ...