The Barcelona International Conference on Advances in Statistics (BAS 2012) : Abstracts of communications

Conferència Organitzada per l'Escola Politècnica Superior, Universitat de Vic en col·laboració amb Servei d'Estadística de la Universitat Autònoma de Barcelona i CosmoCaixa Barcelona. Celebrada del 18 al 22 de juny de 2012 a Barcelona

On cumulant techniques in speech processing

This paper analyzes applications of cumulant analysis in speech processing. A special focus is made on different second-order statistics. A dominant role is played by an integral representation for cumulants by means of integrals involving cyclic products of kernels.

Exploring Non-linear Transformations for an Entropybased Voice Activity Detector

In this paper we explore the use of non-linear transformations in order to improve the performance of an entropy based voice activity detector (VAD). The idea of using a non-linear transformation comes from some previous work done in speech linear prediction (LPC) field based in source separation techniques, where the score function was added into the classical equations in order to take into account the real distribution of the signal. We explore the possibility of estimating the entropy of frames after calculating its score function, instead of using original frames. We observe that if signal is clean, estimated entropy is essentially the same; but if signal is noisy transformed frames (with score function) are able to give different entropy if the frame is voiced against unvoiced ones. Experimental results show that this fact permits to detect voice activity under high noise, where simple entropy method fails.

Improving Pitch Tracking Performance in Hard Noise Conditions by a Preprocessing Based on Mathematical Morphology

In this paper we show how a nonlinear preprocessing of speech signal -with high noise- based on morphological filters improves the performance of robust algorithms for pitch tracking (RAPT). This result happens for a very simple morphological filter. More sophisticated ones could even improve such results. Mathematical morphology is widely used in image processing and has a great amount of applications. Almost all its formulations derived in the two-dimensional framework are easily reformulated to be adapted to one-dimensional context

Spontaneous Speech and Emotional Response modeling based on One-class classifier oriented to Alzheimer Disease diagnosis

The purpose of our project is to contribute to earlier diagnosis of AD and better estimates of its severity by using automatic analysis performed through new biomarkers extracted from non-invasive intelligent methods. The methods selected in this case are speech biomarkers oriented to Sponta-neous Speech and Emotional Response Analysis. Thus the main goal of the present work is feature search in Spontaneous Speech oriented to pre-clinical evaluation for the definition of test for AD diagnosis by One-class classifier. One-class classifi-cation problem differs from multi-class classifier in one essen-tial aspect. In one-class classification it is assumed that only information of one of the classes, the target class, is available. In this work we explore the problem of imbalanced datasets that is particularly crucial in applications where the goal is to maximize recognition of the minority class as in medical diag-nosis. The use of information about outlier and Fractal Dimen-sion features improves the system performance.

Online drawings for dementia diagnose: in-air and pressure information analysis

In this paper we present experimental results comparing on-line drawings for control population (left and right hand) as well as Alzheimer disease patients. The drawings have been acquired by means of a digitizing tablet, which acquires time information angles and pressures. Experimental measures based on pressure and in-air movements appear to be significantly different for both groups, even when control population performs the tasks with the non-dominant hand.

Local perception and use of the multifunctionality of water tanks in two villages of Tamil Nadu, South India

Using data from free listings and a survey in two villages of Tamil Nadu, India, we discuss local perceptions and uses of water tanks, a traditional irrigation infrastructure. We hypothesize that both farmers and nonfarmers perceive and use water tanks for purposes other than irrigation. We found that informants recognized the importance of water tanks for irrigation, but also acknowledged other socioeconomic uses and ecological functions. Marginal sectors (i.e., Scheduled Castes) use tank resources in more diverse ways than other sectors of the population. Findings are relevant for development. International organizations working on the revival of water tanks aim to transfer water management to farmers for the purpose of irrigation. By recognizing that tanks benefit people other than farmers and in ways other than providing irrigation water, organizations working on tank rejuvenation could achieve a more equitable management of tank resources.

Protocol per a la implantació d'eines didàctiques virtuals: competències i habilitats adquirides pels estudiants

L"adaptació al nou espai europeu d"educació superior (EEES) ha plantejat alguns canvis en l"enfocament de la formació universitària al nostre país. On abans era el docent el protagonista, ara és l"estudiant el que pren el rol d"actor principal de la seva formació, i l"aprenentatge s"orienta cap a una autonomia i reflexió més grans. En aquest escenari, les noves tecnologies ofereixen un ampli ventall d"opcions per millorar els processos formatius. En aquests sentit, el Grup d"Innovació Docent G IDEA ha participat activament en aquest procés d"adaptació des de ja fa uns quants anys, i ha creat una sèrie de recursos docents digitals que han estat àmpliament provats en diversos ensenyaments de la Facultat d"Economia i Empresa de la Universitat de Barcelona. L"objectiu d"aquest article és presentar el protocol dissenyat per l"equip d"investigadors del G IDEA per implantar aquestes eines didàctiques (webquestes i exercicis tutoritzats), i també els resultats d"una enquesta de satisfacció sobre les competències i habilitats adquirides pels nostres estudiants en la utilització dels recursos. Els resultats mostren, d"una banda, que no ha estat possible crear un mateix protocol aplicable a tots els recursos, a causa de les diferències en els objectius didàctics de les distintes eines docents implantades. D"altra banda, la valoració que els estudiants fan de la utilització de les eines és molt positiva, tot i que hi ha algunes diferències entre els recursos analitzats. Conèixer la valoració que l"alumnat fa d"aquests recursos permet al grup d"investigadors poder-los millorar i adequar al perfil dels estudiants perquè aquests en puguin treure el màxim profit possible.

Preservación digital en 2009

Se realiza un balance del estado de la investigación y el desarrollo de soluciones en preservación digital a nivel internacional en 2009, así como de las expectativas para 2010. Se presta una especial atención al seguimiento de las principales líneas de investigación y a los desarrollos de software específico, y se caracterizan los centros de investigación preeminentes a nivel mundial.

Las auditorías, una metodología para planificar la preservación digital. Experiencias en España.

Se presentan los resultados obtenidos en la aplicación de diversas metodologías de auditoría para comprobar el estado de la preservación digital en distintas instituciones de España. Se concluye que las auditorías también se pueden usar como herramienta de ayuda a la planificación de sistemas de preservación digital.

Gold or green: the debate on Open Access policies

The movement for open access to science seeks to achieve unrestricted and free access to academic publications on the Internet. To this end, two mechanisms have been established: the gold road, in which scientific journals are openly accessible, and the green road, in which publications are self-archived in repositories. The publication of the Finch Report in 2012, advocating exclusively the adoption of the gold road, generated a debate as to whether either of the two options should be prioritized. The recommendations of the Finch Report stirred controversy among academicians specialized in open access issues, who felt that the role played by repositories was not adequately considered and because the green road places the burden of publishing costs basically on authors. The Finch Report"s conclusions are compatible with the characteristics of science communication in the UK and they could surely also be applied to the (few) countries with a powerful publishing industry and substantial research funding. In Spain, both the current national legislation and the existing rules at universities largely advocate the green road. This is directly related to the structure of scientific communication in Spain, where many journals have little commercial significance, the system of charging a fee to authors has not been adopted, and there is a good repository infrastructure. As for open access policies, the performance of the scientific communication system in each country should be carefully analyzed to determine the most suitable open access strategy. [Int Microbiol 2013; 16(3):199-203]

Tractament digital de la imatge com a suport per a la recerca

La investigació actual necessita recórrer en nombroses ocasions a la imatge, i encara ho podria fer més. El registre d'imatges s'ha convertit avui en una feina senzilla i económica, almenys en relació amb la situació de fa vint anys. I des de fa amb prou feines un parell d'anys, el tractament de la imatge animada mitjançant tècniques digitals encara s'ha simplificat més, alhora que ha proporcionat nous canvis que permeten explorar la realitat.

Broadband prices in the European Union : competition and commercial strategies

This paper analyses the determinants of broadband Internet access prices in a group of 15 EU countries between 2008 and 2011. Using a rich panel dataset of broadband plans, we show the positive effect of downstream speed on prices, and report that cable and fibre-to-the-home technologies are available at lower prices per Mbps than x DSL technology. Operators’marketing strategies are also analysed as we show how much prices rise when the broadband service is offered in a bundle with voice telephony and/or television, and how much they fall when download volume caps are included. The most insightful results of this study are provided by a group of metrics that represent the situation of competition and entry patterns in the broadband market. We show that consumer segmentation positively affects prices. On the other hand, broadband prices are higher in countries where entrants make greater use of bitstream access and lower when they use more intensively direct access -local loop unbundling-. However, we do not find a significant effect of inter-platform competition on prices.

La liberalización de las telecomunicaciones en España : control de la inflación y universalización del servicio

Los estudios sobre la liberalización han enfatizado la importancia de las presiones externas en el impulso a las reformas pro mercado. Sin negar esta influencia, en este trabajo sostenemos que son los intereses nacionales los que determinan la estrategia y ritmos de la liberalización. La liberalización de las telecomunicaciones realizada en España en el período 1987-2003 presenta diferencias significativas respecto a la de otros países de la UE. Esas diferencias están relacionadas con las estrategias que se adoptaron internamente al ver cómo la liberalización podía afectar a los objetivos de política económica general. El artículo destaca la existencia de dos tipos de conflictos. En primer lugar, la tensión entre, por un lado, la necesidad de universalizar el acceso al servicio y, por otro, la de reducir los precios de las telecomunicaciones con el objetivo de controlar la inflación. En segundo lugar, los reformadores españoles tuvieron que escoger entre un modelo de competencia intraplataforma que permitiera a los entrantes utilizar la red de Telefónica a precios reducidos y asegurase rápidas reducciones de precios o un modelo de competencia inter-plataforma que fomentase la inversión, la competencia tecnológica y el bienestar a largo plazo. La consideración de estos conflictos internos es clave para entender la economía política de la política española de telecomunicaciones. Nuestra conclusión es que la liberalización en España se vio frenada cuando entró en conflicto con objetivos de interés general internos, pero se aceleró cuando fue percibida como un instrumento útil para el logro de los interesas nacionales.