Pushdown automata in statistical machine translation

This article describes the use of pushdown automata (PDA) in the context of statistical machine translation and alignment under a synchronous context-free grammar. We use PDAs to compactly represent the space of candidate translations generated by the grammar when applied to an input sentence. General-purpose PDA algorithms for replacement, composition, shortest path, and expansion are presented. We describe HiPDT, a hierarchical phrase-based decoder using the PDA representation and these algorithms. We contrast the complexity of this decoder with a decoder based on a finite state automata representation, showing that PDAs provide a more suitable framework to achieve exact decoding for larger synchronous context-free grammars and smaller language models. We assess this experimentally on a large-scale Chinese-to-English alignment and translation task. In translation, we propose a two-pass decoding strategy involving a weaker language model in the first-pass to address the results of PDA complexity analysis. We study in depth the experimental conditions and tradeoffs in which HiPDT can achieve state-of-the-art performance for large-scale SMT. </jats:p

Analyzing collaborative learning processes automatically

In this article we describe the emerging area of text classification research focused on the problem of collaborative learning process analysis both from a broad perspective and more specifically in terms of a publicly available tool set called TagHelper tools. Analyzing the variety of pedagogically valuable facets of learners’ interactions is a time consuming and effortful process. Improving automated analyses of such highly valued processes of collaborative learning by adapting and applying recent text classification technologies would make it a less arduous task to obtain insights from corpus data. This endeavor also holds the potential for enabling substantially improved on-line instruction both by providing teachers and facilitators with reports about the groups they are moderating and by triggering context sensitive collaborative learning support on an as-needed basis. In this article, we report on an interdisciplinary research project, which has been investigating the effectiveness of applying text classification technology to a large CSCL corpus that has been analyzed by human coders using a theory-based multidimensional coding scheme. We report promising results and include an in-depth discussion of important issues such as reliability, validity, and efficiency that should be considered when deciding on the appropriateness of adopting a new technology such as TagHelper tools. One major technical contribution of this work is a demonstration that an important piece of the work towards making text classification technology effective for this purpose is designing and building linguistic pattern detectors, otherwise known as features, that can be extracted reliably from texts and that have high predictive power for the categories of discourse actions that the CSCL community is interested in

From Mexico to Beijing: "Women in Development" Twenty Five Years On

During the past twenty five years the Women in Development (WID)approach has become an increasingly important issue in the literature on Third World development. WID issues and related activities have now been incorporated into the aid practice of most development agencies. This paper critically analyses the diverse and conflicting ideologies that have emerged in the WID literature since the early seventies

Back to the past: the individual and its role in creativity in organisations

O objetivo deste texto é realçar o papel do indivíduo na criatividade nas organizações. Esse papel tem sido estranhamente remetido para um plano secundário, à medida que as modernas visões da criatividade a definem, sobretudo, com relação ao contexto em que ocorre. De fato, na perspectiva atual, a criatividade não pode ser entendida sem se considerarem os contextos funcional, relacional e organizacional nos quais está inserido o trabalhador. Tais são as considerações da maior parte dos autores que escreve sobre o tópico, como sejam Amabile (1996), Csikszentmihalyi (1996), ou, mais recentemente, Glăveanu (2010a, 2010b). Essa corrente dominante, com origem no interacionismo psico-social, tem ainda influenciado o desenvolvimento teórico de outros conceitos em psicologia, sociologia, e, na sequência, nas ciências sociais e humanas, e na gestão. Essa supremacia no que concerne a criatividade, tem conduzido os autores a olvidar o papel do indivíduo no processo e no resultado criativos, chegando a retirar-lhe a responsabilidade e o protagonismo pela geração e produção de ideias. Desse modo, no presente texto, recuperam-se os argumentos em favor da centralidade da pessoa na criatividade, defendendo-se que esta tem uma existência isolada de influências externas, e que, como tal, devem relembrar-se as bases individuais da criatividadeThe goal of the current text is to highlight the role of the individual in creativity in organisations. This role has been strangely disregarded in recent years, as modern accounts of creativity have been emphasising the idea that creativity is only defined in context. This main stream argues that creativity is a process that essentially occurs within a functional, relational, and organisational context in which workers are inserted. Key authors defending such a position include the likes of Amabile (1996), Csikszentmihalyi (1996), and, more recently, Glăveanu (2010a, 2010b). This is a vision rooted in the psychosocial interactionist perspective, which has also had a considerable impact in other areas in psychology, sociology, management and other social and human sciences. This supremacy, with regards to creativity, has led many to forget the role of the individual person in the creative process and output, removing their responsibility and protagonism for generating and producing ideas. Hence, the current text intends to bring back to discussion the individual bases of creativity, that people can have an existence isolated from external influences, further defending that the concept can and should be defined out of context, rather than in contextinfo:eu-repo/semantics/publishedVersio

Spoken term detection ALBAYZIN 2014 evaluation: overview, systems, results, and discussion

The electronic version of this article is the complete one and can be found online at: http://dx.doi.org/10.1186/s13636-015-0063-8Spoken term detection (STD) aims at retrieving data from a speech repository given a textual representation of the search term. Nowadays, it is receiving much interest due to the large volume of multimedia information. STD differs from automatic speech recognition (ASR) in that ASR is interested in all the terms/words that appear in the speech data, whereas STD focuses on a selected list of search terms that must be detected within the speech data. This paper presents the systems submitted to the STD ALBAYZIN 2014 evaluation, held as a part of the ALBAYZIN 2014 evaluation campaign within the context of the IberSPEECH 2014 conference. This is the first STD evaluation that deals with Spanish language. The evaluation consists of retrieving the speech files that contain the search terms, indicating their start and end times within the appropriate speech file, along with a score value that reflects the confidence given to the detection of the search term. The evaluation is conducted on a Spanish spontaneous speech database, which comprises a set of talks from workshops and amounts to about 7 h of speech. We present the database, the evaluation metrics, the systems submitted to the evaluation, the results, and a detailed discussion. Four different research groups took part in the evaluation. Evaluation results show reasonable performance for moderate out-of-vocabulary term rate. This paper compares the systems submitted to the evaluation and makes a deep analysis based on some search term properties (term length, in-vocabulary/out-of-vocabulary terms, single-word/multi-word terms, and in-language/foreign terms).This work has been partly supported by project CMC-V2 (TEC2012-37585-C02-01) from the Spanish Ministry of Economy and Competitiveness. This research was also funded by the European Regional Development Fund, the Galician Regional Government (GRC2014/024, “Consolidation of Research Units: AtlantTIC Project” CN2012/160)

History Shaped the Geographic Distribution of Genomic Admixture on the Island of Puerto Rico

Contemporary genetic variation among Latin Americans human groups reflects population migrations shaped by complex historical, social and economic factors. Consequently, admixture patterns may vary by geographic regions ranging from countries to neighborhoods. We examined the geographic variation of admixture across the island of Puerto Rico and the degree to which it could be explained by historic and social events. We analyzed a census-based sample of 642 Puerto Rican individuals that were genotyped for 93 ancestry informative markers (AIMs) to estimate African, European and Native American ancestry. Socioeconomic status (SES) data and geographic location were obtained for each individual. There was significant geographic variation of ancestry across the island. In particular, African ancestry demonstrated a decreasing East to West gradient that was partially explained by historical factors linked to the colonial sugar plantation system. SES also demonstrated a parallel decreasing cline from East to West. However, at a local level, SES and African ancestry were negatively correlated. European ancestry was strongly negatively correlated with African ancestry and therefore showed patterns complementary to African ancestry. By contrast, Native American ancestry showed little variation across the island and across individuals and appears to have played little social role historically. The observed geographic distributions of SES and genetic variation relate to historical social events and mating patterns, and have substantial implications for the design of studies in the recently admixed Puerto Rican population. More generally, our results demonstrate the importance of incorporating social and geographic data with genetics when studying contemporary admixed populations