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Constant for associative patterns ensemble

arXiv.org Artificial Intelligence

Creation procedure of associative patterns ensemble in terms of formal logic with using neural net-work (NN) model is formulated. It is shown that the associative patterns set is created by means of unique procedure of NN work which having individual parameters of entrance stimulus transformation. It is ascer-tained that the quantity of the selected associative patterns possesses is a constant.


Community Detection in Complex Networks Using Agents

arXiv.org Artificial Intelligence

Community structure identification has been one of the most popular research areas in recent years due to its applicability to the wide scale of disciplines. To detect communities in varied topics, there have been many algorithms proposed so far. However, most of them still have some drawbacks to be addressed. In this paper, we present an agent-based based community detection algorithm. The algorithm that is a stochastic one makes use of agents by forcing them to perform biased moves in a smart way. Using the information collected by the traverses of these agents in the network, the network structure is revealed. Also, the network modularity is used for determining the number of communities. Our algorithm removes the need for prior knowledge about the network such as number of the communities or any threshold values. Furthermore, the definite community structure is provided as a result instead of giving some structures requiring further processes. Besides, the computational and time costs are optimized because of using thread like working agents. The algorithm is tested on three network data of different types and sizes named Zachary karate club, college football and political books. For all three networks, the real network structures are identified in almost every run.


Fitness Uniform Optimization

arXiv.org Artificial Intelligence

In evolutionary algorithms, the fitness of a population increases with time by mutating and recombining individuals and by a biased selection of more fit individuals. The right selection pressure is critical in ensuring sufficient optimization progress on the one hand and in preserving genetic diversity to be able to escape from local optima on the other hand. Motivated by a universal similarity relation on the individuals, we propose a new selection scheme, which is uniform in the fitness values. It generates selection pressure toward sparsely populated fitness regions, not necessarily toward higher fitness, as is the case for all other selection schemes. We show analytically on a simple example that the new selection scheme can be much more effective than standard selection schemes. We also propose a new deletion scheme which achieves a similar result via deletion and show how such a scheme preserves genetic diversity more effectively than standard approaches. We compare the performance of the new schemes to tournament selection and random deletion on an artificial deceptive problem and a range of NP-hard problems: traveling salesman, set covering and satisfiability.


Dependency Treebanks: Methods, Annotation Schemes and Tools

arXiv.org Artificial Intelligence

In this paper, current dependency-based treebanks are introduced and analyzed. The methods used for building the resources, the annotation schemes applied, and the tools used (such as POS taggers, parsers and annotation software) are discussed.


Applying Part-of-Seech Enhanced LSA to Automatic Essay Grading

arXiv.org Artificial Intelligence

Latent Semantic Analysis (LSA) is a widely used Information Retrieval method based on "bag-of-words" assumption. However, according to general conception, syntax plays a role in representing meaning of sentences. Thus, enhancing LSA with part-of-speech (POS) information to capture the context of word occurrences appears to be theoretically feasible extension. The approach is tested empirically on a automatic essay grading system using LSA for document similarity comparisons. A comparison on several POS-enhanced LSA models is reported. Our findings show that the addition of contextual information in the form of POS tags can raise the accuracy of the LSA-based scoring models up to 10.77 per cent.


DepAnn - An Annotation Tool for Dependency Treebanks

arXiv.org Artificial Intelligence

DepAnn is an interactive annotation tool for dependency treebanks, providing both graphical and text-based annotation interfaces. The tool is aimed for semi-automatic creation of treebanks. It aids the manual inspection and correction of automatically created parses, making the annotation process faster and less error-prone. A novel feature of the tool is that it enables the user to view outputs from several parsers as the basis for creating the final tree to be saved to the treebank. DepAnn uses TIGER-XML, an XML-based general encoding format for both, representing the parser outputs and saving the annotated treebank. The tool includes an automatic consistency checker for sentence structures. In addition, the tool enables users to build structures manually, add comments on the annotations, modify the tagsets, and mark sentences for further revision.


CHAC. A MOACO Algorithm for Computation of Bi-Criteria Military Unit Path in the Battlefield

arXiv.org Artificial Intelligence

In this paper we propose a Multi-Objective Ant Colony Optimization (MOACO) algorithm called CHAC, which has been designed to solve the problem of finding the path on a map (corresponding to a simulated battlefield) that minimizes resources while maximizing safety. CHAC has been tested with two different state transition rules: an aggregative function that combines the heuristic and pheromone information of both objectives and a second one that is based on the dominance concept of multiobjective optimization problems. These rules have been evaluated in several different situations (maps with different degree of difficulty), and we have found that they yield better results than a greedy algorithm (taken as baseline) in addition to a military behaviour that is also better in the tactical sense. The aggregative function, in general, yields better results than the one based on dominance.


Characterizing Solution Concepts in Games Using Knowledge-Based Programs

arXiv.org Artificial Intelligence

We show how solution concepts in games such as Nash equilibrium, correlated equilibrium, rationalizability, and sequential equilibrium can be given a uniform definition in terms of \emph{knowledge-based programs}. Intuitively, all solution concepts are implementations of two knowledge-based programs, one appropriate for games represented in normal form, the other for games represented in extensive form. These knowledge-based programs can be viewed as embodying rationality. The representation works even if (a) information sets do not capture an agent's knowledge, (b) uncertainty is not represented by probability, or (c) the underlying game is not common knowledge.


Solving planning domains with polytree causal graphs is NP-complete

arXiv.org Artificial Intelligence

It is well known that the planning problem (namely, the probl em of obtaining a valid sequence of transformations that moves a sys tem from an initial state to a goal state) is intractable in general [3]. However, it is widely believed that many real-life problems have a particu lar structure, and that by exploiting this structure general planners will be able to efficiently handle more meaningful problems. One of the most fruitful tools researchers have been using to characterize structure in planning problems is the so called causal graph ([6]). In short, the causal graph of a problem instance is a graph that c aptures the degree of interdependence among the state variables of the p roblem.The causal graph has been used both as a tool for describing tract able subclasses of planning problems (e.g., [7], [2], [4]) and as a ke y property which algorithms that adress the general planning problem take in to consideration [5]. In the present work we show that solving planning domains whe re the causal graph is a polytree (that is, the underlying undir ected graph is acyclic) is NP-complete, even if we restrict to domains wi th binary variables and unary operators. This result closes the compl exity gap that appears in [4], where it is shown that plan existence is NP-co mplete for planning domains with singly connected causal graphs, and t hat plan generation is polynomial for planning domains with polytre e causal graphs of bounded indegree. Additionally, it is known that solving unary operator plann ing problems on binary variables is essentially equivalent to solvi ng dominance queries for binary-valued CP-nets (see [1]). Under this ref ormulation the causal graph becomes the CP-net, so the present work also sho ws that dominance testing for binary-valued polytree CP-nets is NP -complete.


On Geometric Algebra representation of Binary Spatter Codes

arXiv.org Artificial Intelligence

Distributed representation is a way of representing information in a pattern of activation over a set of neurons, in which each concept is represented by activation over multiple neuro ns, and each neuron participates in the representation of multiple concepts [1]. Examples of distributed representat ions include Recursive Auto-Associative Memory (RAAM) [2], Tensor Product Representations [3], Holographic Reduc ed Representations (HRRs) [4, 5], and Binary Spatter Codes (BSC) [6, 7, 8]. BSC is a powerful and simple method of representing hierarchical st ructures in connectionist systems and may be regarded as a binary version of HRRs. Yet, BSC has some drawback s associated with the representation of chunking. This is why different versions of BSC can be found in the literature.