Search results for "semantic analysis"
showing 10 items of 56 documents
Fostering Teacher-Student Interaction and Learner Autonomy by the I-TUTOR Maps
2014
The paper analyses the use of an automatically generated map as a mediator; that map visually represents the study domain of a university course and fosters the co-activity between teachers and stu- dents. In our approach the role of the teacher is meant as a media- tor between the student and knowledge. The mediation (and not the transmission) highlights a process in which theres no deterministic rela- tion between teaching and learning. Learning is affected by the students previous experiences, their own modalities of acquisition and by the in- puts coming from the environment. The learning path develops when the teachers and the students visions approach and, partly, overlap. In this cas…
A Geometric Algebra Based Distributional Model to Encode Sentences Semantics
2013
Word space models are used to encode the semantics of natural language elements by means of high dimensional vectors [23]. Latent Semantic Analysis (LSA) methodology [15] is well known and widely used for its generalization properties. Despite of its good performance in several applications, the model induced by LSA ignores dynamic changes in sentences meaning that depend on the order of the words, because it is based on a bag of words analysis. In this chapter we present a technique that exploits LSA-based semantic spaces and geometric algebra in order to obtain a sub-symbolic encoding of sentences taking into account the words sequence in the sentence. © 2014 Springer-Verlag Berlin Heidel…
Clifford Rotors for Conceptual Representation in Chatbots
2013
In this abstract we introduce an unsupervised sub-symbolic natural language sentences encoding procedure aimed at catching and representing into a Chatbot Knowledge Base (KB) the concepts expressed by an user interacting with a robot. The chatbot KB is coded in a conceptual space induced from the application of the Latent Semantic Analysis (LSA) paradigm on a corpus of documents. LSA has the effect of decomposing the original relationships between elements into linearly-independent vectors. Each basis vector can be considered therefore as a "conceptual coordinate", which can be tagged by the words which better characterize it. This tagging is obtained by performing a (TF-IDF)-like weighting…
TSVD as a Statistical Estimator in the Latent Semantic Analysis Paradigm
2015
The aim of this paper is to present a new point of view that makes it possible to give a statistical interpretation of the traditional latent semantic analysis (LSA) paradigm based on the truncated singular value decomposition (TSVD) technique. We show how the TSVD can be interpreted as a statistical estimator derived from the LSA co-occurrence relationship matrix by mapping probability distributions on Riemanian manifolds. Besides, the quality of the estimator model can be expressed by introducing a figure of merit arising from the Solomonoff approach. This figure of merit takes into account both the adherence to the sample data and the simplicity of the model. In our model, the simplicity…
AN ARCHITECTURE FOR HUMANOID ROBOT EXPRESSING EMOTIONS AND PERSONALITY
2010
In this paper we illustrate the cognitive architecture of a humanoid robot based on the proposed paradigm of Latent Semantic Analysis (LSA). The LSA approach allows the creation and the use of a data driven high-dimensional conceptual space. This paradigm is a step towards the simulation of an emotional behavior of a robot interacting with humans. The Architecture is organized in three main areas: Sub-conceptual, Emotional and Behavioral. The first area processes perceptual data coming from the sensors. The second area is the “conceptual space of emotional states” which constitutes the sub-symbolic representation of emotions. The last area activates a latent semantic behavior related to the…
Knowledge Representation in Empathic Robots-Rappresentazione della conoscenza in robot empatici
2011
In questo articolo si illustra l'architettura cognitiva di un robot umanoide basato sul paradigma della Latent Semantic Analysis (LSA). L'approccio LSA consente la creazione e l'utilizzo di un spazio concettuale multi-dimensionale e data driven. Questo paradigma è un passo verso la simulazione di un comportamento emotivo di un robot che interagisce con gli umani. L'architettura è organizzata in tre aree principali: Subconcettuale, emotivo e comportamentale. La prima area elabora i dati percettivi provenienti dai sensori. La seconda area è lo "spazio concettuale di stati emotivi" che costituisce la rappresentazione sub-simbolica di emozioni. L'ultima area attiva un comportamento semantico la…
An emotional humanoid partner
2010
In this paper we propose an emotional humanoid robot based on Latent Semantic Analysis, that exhibits an emotional behaviour in the interaction with human. Latent Semantic Analysis (LSA) paradigm is capable to encode the semantics of words using a statistical computation of a large corpus of text. We illustrate how the creation and the use of this emotional conceptual space allows the building of “Latent Semantic Behaviour” because it simulates the emotional associative capabilities of human beings. The presented approach integrates traditional knowledge representation and intuitive capabilities provided by geometric and sub-symbolic information modelling. To validate the effectiveness of t…
A Conceptual Probabilistic Model for the Induction of Image Semantics
2010
In this paper we propose a model based on a conceptual space automatically induced from data. The model is inspired to a well-founded robotics cognitive architecture which is organized in three computational areas: sub-conceptual, linguistic and conceptual. Images are objects in the sub-conceptual area, that become "knoxels" into the conceptual area. The application of the framework grants the automatic emerging of image semantics into the linguistic area. The core of the model is a conceptual space induced automatically from a set of annotated images that exploits and mixes different information concerning the set of images. Multiple low level features are extracted to represent images and…
A Semantic Similarity Measure for the SIMS Framework
2008
The amount of currently available digital information grows rapidly. Relevant information is often spread over different information sources. An efficient and flexible framework to allow users to satisfy ef- fectively their information needs is required. The work presented in this paper describes SIMS (Semantic Information Management System), a ref- erence architecture for a framework performing semantic annotation, search and retrieval of information from multiple sources. The work pre- sented in this paper focuses on a specific SIMS module, the SIMS Semantic Content Navigator, proposing an algorithm and the related implementa- tion to calculate a semantic similarity measure inside an OWL …
A Cognitive Dialogue Manager for Education Purposes
2011
A conversational agent is a software system that is able to interact with users in a natural way, and often uses natural language capabilities. In this chapter, an evolution of a conversational agent is presented according to the definition of dialogue management techniques for the conversational agents. The presented conversational agent is intended to act as a part of an educational system. The chapter outlines the state-of-the-art systems and techniques for dialogue management in cognitive educational systems, and the underlying psychological and social aspects. We present our framework for a dialogue manager aimed to reduce the uncertainty in users’ sentences during the assessment of hi…