Publicaciones

RL5, Publisher: Social Network Analysis and Mining, Link>

AUTHORS

Eliana Providel, Marcelo Mendoza

ABSTRACT

Misleading information spread on social networks is often supported by activists who promote this type of information and bots that amplify their visibility. The need for useful and timely mechanisms of credibility assessment in social media has become increasingly indispensable. Efforts to tackle this problem in Spanish are growing. The last years have witnessed many efforts to develop methods to detect fake news, rumors, stances, and bots on the Spanish social web. This work leads to a systematic review of the literature that relates the efforts to develop this area in the Spanish language. The work identifies pending tasks for this community and challenges that require coordination among the leading investigators on the subject.


86 visualizaciones Ir a la publicación

RL5, Publisher: Publications, Link>

AUTHORS

Marcelo Mendoza

ABSTRACT

The evaluation of research proposals and academic careers is subject to indicators of scientific productivity. Citations are critical signs of impact for researchers, and many indicators are based on these data. The literature shows that there are differences in citation patterns between areas. The scope and depth that these differences may have to motivate the extension of these studies considering types of articles and age groups of researchers. In this work, we conducted an exploratory study to elucidate what evidence there is about the existence of these differences in citation patterns. To perform this study, we collected historical data from Scopus. Analyzing these data, we evaluate if there are measurable differences in citation patterns. This study shows that there are evident differences in citation patterns between areas, types of publications, and age groups of researchers that may be relevant when carrying out researchers’ academic evaluation.


89 visualizaciones Ir a la publicación

RL3, Publisher: Cognition, Link>

AUTHORS

Guedes B, Nespor M, Peña Garay M, Saksida A, Flo A

ABSTRACT

One of the prominent ideas developed by Jacques Mehler and his colleagues was that perceptual tuning, present from birth on, enables infants, and language learners in general, to extract regularities from speech input. Here we discuss language learners'' ability to extract basic word order (VO or OV) structure from prosodic regularities in a language. The two are closely related: in phonological phrases of VO languages, the most prominent word is the rightmost one, and in OV languages, it is the leftmost one. In speech, this prominence is realized as extended duration, or as elevated pitch, sometimes combined with changes in intensity. When learning the first (L1) or the second language (L2), exposure to relevant rhythmic structure elicits implicit learning about syntactic structure, including the basic word order. However, it remains unclear whether triggering the learning process requires a certain level of familiarity with the relevant rhythm. It is moreover unknown whether prosodic information can help L2 learners to extract and learn the vocabulary of a new language. We tested Spanish- and Italian-speaking adults' ability to learn words from an artificial language with either non-native OV or native VO word order. The results show that learners used prosodic information to identify the most prominent words in short utterances when the artificial language was similar to the native language, with duration-based prominence in prosody and a VO word order. In contrast, when the artificial language had a non-native prominence marked by pitch alternations and an OV word order, prominent words were learned only after a three-day exposure to the relevant rhythmic structure. Thus, for adult L2 learners, only repeated exposure to the relevant prosody elicited learning new words from an unknown language with non-native prosodic marking, indicating that, with familiarity, prosodic cues can facilitate learning in L2.


169 visualizaciones Ir a la publicación

RL3, Publisher: Scientific Reports, Link>

AUTHORS

Jara C, Moenne C, Peña M

ABSTRACT

Before the 6-months of age, infants succeed to learn words associated with objects and actions when the words are presented isolated or embedded in short utterances. It remains unclear whether such type of learning occurs from fluent audiovisual stimuli, although in natural environments the fluent audiovisual contexts are the default. In 4 experiments, we evaluated if 8-month-old infants could learn word-action and word-object associations from fluent audiovisual streams when the words conveyed either vowel or consonant harmony, two phonological cues that benefit word learning near 6 and 12 months of age, respectively. We found that infants learned both types of words, but only when the words contained vowel harmony. Because object- and action-words have been conceived as rudimentary representations of nouns and verbs, our results suggest that vowels contribute to shape the initial steps of the learning of lexical categories in preverbal infants.


117 visualizaciones Ir a la publicación

RL3, Publisher: PNAS, Link>

AUTHORS

J F, M & Werker, G Peña, Dehaene-Lambertz, Choi D

ABSTRACT

While there is increasing acceptance that even young infants detect correspondences between heard and seen speech, the common view is that oral-motor movements related to speech production cannot influence speech perception until infants begin to babble or speak. We investigated the extent of multimodal speech influences on auditory speech perception in prebabbling infants who have limited speech-like oral-motor repertoires. We used event-related potentials (ERPs) to examine how sensorimotor influences to the infant’s own articulatory movements impact auditory speech perception in 3-mo-old infants. In experiment 1, there were ERP discriminative responses to phonetic category changes across two phonetic contrasts (bilabial–dental /ba/-/ɗa/; dental–retroflex /ɗa/-/ɖa/) in a mismatch paradigm, indicating that infants auditorily discriminated both contrasts. In experiment 2, inhibiting infants’ own tongue-tip movements had a disruptive influence on the early ERP discriminative response to the /ɗa/-/ɖa/ contrast only. The same articulatory inhibition had contrasting effects on the perception of the /ba/-/ɗa/ contrast, which requires different articulators (the lips vs. the tongue) during production, and the /ɗa/-/ɖa/ contrast, whereby both phones require tongue-tip movement as a place of articulation. This articulatory distinction between the two contrasts plausibly accounts for the distinct influence of tongue-tip suppression on the neural responses to phonetic category change perception in definitively prebabbling, 3-mo-old, infants. The results showing a specificity in the relation between oral-motor inhibition and phonetic speech discrimination suggest a surprisingly early mapping between auditory and motor speech representation already in prebabbling infants.


109 visualizaciones Ir a la publicación

RL3, Publisher: Cognition, Link>

AUTHORS

Gouet C, Halberda, J, Jin W, M, Naiman, Peña, D Q

ABSTRACT

The importance of proportional reasoning has long been recognized by psychologists and educators, yet we still do not have a good understanding of how humans mentally represent proportions. In this paper we present a psychophysical model of proportion estimation, extending previous approaches. We assumed that proportion representations are formed by representing each magnitude of a proportion stimuli (the part and its complement) as Gaussian activations in the mind, which are then mentally combined in the form of a proportion. We next derived the internal representation of proportions, including bias and internal noise parameters -capturing respectively how our estimations depart from true values and how variable estimations are. Methodologically, we introduced a mixture of components to account for contaminating behaviors (guessing and reversal of responses) and framed the model in a hierarchical way. We found empirical support for the model by testing a group of 4th grade children in a spatial proportion estimation task. In particular, the internal density reproduced the asymmetries (skewedness) seen in this and in previous reports of estimation tasks, and the model accurately described wide variations between subjects in behavior. Bias estimates were in general smaller than by using previous approaches, due to the model's capacity to absorb contaminating behaviors. This property of the model can be of especial relevance for studies aimed at linking psychophysical measures with broader cognitive abilities. We also recovered higher levels of noise than those reported in discrimination of spatial magnitudes and discuss possible explanations for it. We conclude by illustrating a concrete application of our model to study the effects of scaling in proportional reasoning, highlighting the value of quantitative models in this field of research.


154 visualizaciones Ir a la publicación

RL2, Publisher: Carleton University School of Computer Science Ottawa, Link>

AUTHORS

Leopoldo Bertossi

ABSTRACT

Virtual Data Integration Page 1 Virtual Data Integration Leopoldo Bertossi Carleton University School of Computer Science Ottawa, Canada www.scs.carleton.ca/ ∼ bertossi [email protected] Page 2 Chapter 1: Introduction and Issues Page 3 3 Data in Different Forms There is a large and increasing number of data sources People and companies need to integrate data and the systems that handle that data Data in DBMSs: relational, OO, XML, ... Legacy data in different formats and systems Text files repositories Spread sheets Page 4 4 Data on the Web • Non- and semi-structured data in the WWW: Plain text files, HTML text files, native XML • Organizational databases • Libraries, catalogues, etc. • Data in research repositories: genome databases, scientific databases, environmental databases, etc. • Web services • Semantic Web • Knowledge-Based Systems • Ontologies: Structurally and semantically reach do…

 

110 visualizaciones Ir a la publicación

RL2, Publisher: Schloss Dagstuhl-Leibniz-Zentrum für Informatik, Link>

AUTHORS

Gyula OH Katona, Klaus-Dieter Schewe, Leopoldo Bertossi, Bernhard Thalheim

ABSTRACT

In the early days of database research, issues related to database semantics played a prominent role, and papers discussing database models, conceptual design, integrity constraints, normalization often dominated major database conferences. This began to change more than a decade ago, and nowadays those issues do not appear to be part of the mainstream database research. This situation is caused by several reasons: the problem began to be too difficult, the community was hoping on solutions based on better database models, the variety of buzzwords for new models and approaches required foundation and clarification, the problems raised by application required a lot of research, the pending hope on a universal, simple and genius solutions. Nevertheless the semantical foundations are left open for most of the modern database models or are not existing for models such as UML or XML. At the same time, the community was forgetting the achievements of the early database research. The seminar" Semantics in databases" will be a forum for researchers still interested in database semantics and which can contribute on the basis of research on database semantics and modern approaches of logics, algebra and combinatorics to the solution of very difficult problems raised in application. The first workshop" Semantics in Databases" has been organized in Rez in January 1995. The results of the discussions of the workshop have been summarized in the post workshop proceedings published in LNCS 1358. Semantics of databases and information systems can be based on approaches which have been developed and successfully used …


129 visualizaciones Ir a la publicación

RL2, Publisher: Schloss Dagstuhl-Leibniz-Zentrum für Informatik, Link>

AUTHORS

Torsten Schaub, Leopoldo Bertossi, Philippe Besnard, Anthony Hunter

ABSTRACT

Database, Knowledgebase and Software systems, or their logical specifications, may become inconsistent in the sense of containing contradictory pieces of information. Since these types of technology are at some level based on classical logic, there is the major problem that in classical logic, any formula is implied by a contradiction. This therefore raises the need to circumvent this fundamental property of classical logic whilst supporting as much as possible of classical logic for these technologies. To address this, several new logics, with new formalisms, semantics and/or deductive systems, that can accommodate classical inconsistencies without becoming trivial, have been proposed. These logics are starting to be used in databases, knowledgebases and software specifications. In addition, we need strategies for analysing inconsistent information. This need has in part driven the approach of argumentation systems which compare pros and cons for potential conclusions from conflicting information. Also important are strategies for isolating inconsistency and for taking appropriate actions, including resolution actions. This calls for uncertainty reasoning and meta-level reasoning. Furthermore, the cognitive activities involved in reasoning with inconsistent information need to be directly related to the kind of inconsistency. So, in general, we see the need for inconsistency tolerance giving rise to a range of technologies for inconsistency management. We are now at an exciting stage in this direction. Rich foundations are being established, and a number of interesting and complementary application areas are being explored in decision-support …


118 visualizaciones Ir a la publicación

RL2, Publisher: Knowledge and Information Systems, Link>

AUTHORS

Leopoldo Bertossi

ABSTRACT

There is a recently established correspondence between database tuples as causes for query answers in databases and tuple-based repairs of inconsistent databases with respect to denial constraints. In this work, answer-set programs that specify database repairs are used as a basis for solving computational and reasoning problems around causality in databases, including causal responsibility. Furthermore, causes are introduced also at the attribute level by appealing to an attribute-based repair semantics that uses null values. Corresponding repair-programs are introduced, and used as a basis for computation and reasoning about attribute-level causes. The answer-set programs are extended in order to capture causality under integrity constraints.


87 visualizaciones Ir a la publicación