Search results for "Machine learning"

Learning vector quantization with alternative distance criteria

2003

An adaptive algorithm for training of a nearest neighbour (NN) classifier is developed in this paper. This learning rule has some similarity to the well-known LVQ method, but uses the nearest centroid neighbourhood concept to estimate optimal locations of the codebook vectors. The aim of this approach is to improve the performance of the standard LVQ algorithms when using a very small codebook. The behaviour of the learning technique proposed here is experimentally compared to those of the plain k-NN decision rule and the LVQ algorithms.

Las funciones interactivas del marcador español ‘¿no?’ Las fronteras entre la atenuación y la protección de la imagen

2020

In this paper the functions of the Spanish discourse marker ?no? are analysed from a pragmatic and an interactive perspective. Specifically, we explore the values of ?no? taking the pragmatic phenomena of mitigation and boosting, as well as the notion of affiliation as described in conversation analysis. The previous literature devoted to the study of this linguistic form has consistently identified its uses as a confirmation request or a phatic device (Fuentes, 1990, 2009; Santos Rio, 2003; Garcia Vizcaino, 2005; Montanez, 2008, 2015; Rodriguez Munoz, 2009; Moccero, 2010; Santana, 2017). This work, however, analyses how the mitigating uses interact and share features with neighbouring cate…

Modeling Listeners’ Emotional Response to Music

2012

An overview of the computational prediction of emotional responses to music is presented. Communication of emotions by music has received a great deal of attention during the last years and a large number of empirical studies have described the role of individual features (tempo, mode, articulation, timbre) in predicting the emotions suggested or invoked by the music. However, unlike the present work, relatively few studies have attempted to model continua of expressed emotions using a variety of musical features from audio-based representations in a correlation design. The construction of the computational model is divided into four separate phases, with a different focus for evaluation. T…

Les eines computacionals i el disseny de corpus orals: un diàleg vigent

2020

The design of an oral corpus and the processes of registering, codifying and treating the materials in order to build a useful resource for linguistic analysis prompt numerous decisions regarding theory and methodology. This article is focused on those stages of corpus construction which are more clearly conditioned by the computational processing necessary to make it functional. In order to adequately match the initial expectations and the real possibilities of using the tool, each feature we intend to codify must be measured against the workload and the means required to do so. Therefore, it is essential to take into account the available possibilities of processing and exploitation as th…

The Scree Test and the Number of Factors: a Dynamic Graphics Approach

2015

Exploratory Factor Analysis and Principal Component Analysis are two data analysis methods that are commonly used in psychological research. When applying these techniques, it is important to determine how many factors to retain. This decision is sometimes based on a visual inspection of the Scree plot. However, the Scree plot may at times be ambiguous and open to interpretation. This paper aims to explore a number of graphical and computational improvements to the Scree plot in order to make it more valid and informative. These enhancements are based on dynamic and interactive data visualization tools, and range from adding Parallel Analysis results to "linking" the Scree plot with other g…

'The Drawing on the Margin of Cambridge, Corpus Christi College 206, F. 38R: An Intertextual Exemplification to Clarify the Text?'

2007

Video-Based Depression Detection Using Local Curvelet Binary Patterns in Pairwise Orthogonal Planes

2016

International audience; Depression is an increasingly prevalent mood disorder. This is the reason why the field of computer-based depression assessment has been gaining the attention of the research community during the past couple of years. The present work proposes two algorithms for depression detection, one Frame-based and the second Video-based, both employing Curvelet transform and Local Binary Patterns. The main advantage of these methods is that they have significantly lower computational requirements, as the extracted features are of very low dimensionality. This is achieved by modifying the previously proposed algorithm which considers Three-Orthogonal-Planes, to only Pairwise-Ort…

Brain-predicted age difference score is related to specific cognitive functions: A multi-site replication analysis

2021

Abstract Brain-predicted age difference scores are calculated by subtracting chronological age from ‘brain’ age. Positive scores reflect accelerated ageing and are associated with increased mortality risk and poorer physical function. To date, however, the relationship between brain-predicted age difference scores and specific cognitive functions has not been systematically examined. First, applying machine learning to 1,359 T1-weighted MRI scans, we predicted the relationship between chronological age and voxel-wise grey matter data. This model was then applied to MRI data from three independent datasets, significantly predicting chronological age: Dokuz Eylul University (n=175), the Cogni…

The Engineering of a Compression Boosting Library: Theory vs Practice in BWT Compression

2006

Data Compression is one of the most challenging arenas both for algorithm design and engineering. This is particularly true for Burrows and Wheeler Compression a technique that is important in itself and for the design of compressed indexes. There has been considerable debate on how to design and engineer compression algorithms based on the BWT paradigm. In particular, Move-to-Front Encoding is generally believed to be an "inefficient " part of the Burrows-Wheeler compression process. However, only recently two theoretically superior alternatives to Move-to-Front have been proposed, namely Compression Boosting and Wavelet Trees. The main contribution of this paper is to provide the first ex…

From First Principles to the Burrows and Wheeler Transform and Beyond, via Combinatorial Optimization

2007

AbstractWe introduce a combinatorial optimization framework that naturally induces a class of optimal word permutations with respect to a suitably defined cost function taking into account various measures of relatedness between words. The Burrows and Wheeler transform (bwt) (cf. [M. Burrows, D. Wheeler, A block sorting lossless data compression algorithm, Technical Report 124, Digital Equipment Corporation, 1994]), and its analog for labelled trees (cf. [P. Ferragina, F. Luccio, G. Manzini, S. Muthukrishnan, Structuring labeled trees for optimal succinctness, and beyond, in: Proc. of the 45th Annual IEEE Symposium on Foundations of Computer Science, 2005, pp. 198–207]), are special cases i…