1,594 research outputs found
Term-driven E-Commerce
Die Arbeit nimmt sich der textuellen Dimension des E-Commerce an. Grundlegende Hypothese ist die textuelle Gebundenheit von Information und Transaktion im Bereich des elektronischen Handels. Überall dort, wo Produkte und Dienstleistungen angeboten, nachgefragt, wahrgenommen und bewertet werden, kommen natürlichsprachige Ausdrücke zum Einsatz. Daraus resultiert ist zum einen, wie bedeutsam es ist, die Varianz textueller Beschreibungen im E-Commerce zu erfassen, zum anderen können die umfangreichen textuellen Ressourcen, die bei E-Commerce-Interaktionen anfallen, im Hinblick auf ein besseres Verständnis natürlicher Sprache herangezogen werden
Usability evaluation of digital libraries: a tutorial
This one-day tutorial is an introduction to usability evaluation for Digital
Libraries. In particular, we will introduce Claims Analysis. This approach
focuses on the designers’ motivations and reasons for making particular
design decisions and examines the effect on the user’s interaction with
the system. The general approach, as presented by Carroll and
Rosson(1992), has been tailored specifically to the design of digital
libraries.
Digital libraries are notoriously difficult to design well in terms of their
eventual usability. In this tutorial, we will present an overview of
usability issues and techniques for digital libraries, and a more detailed
account of claims analysis, including two supporting techniques –
simple cognitive analysis based on Norman’s ‘action cycle’ and
Scenarios and personas. Through a graduated series of worked
examples, participants will get hands-on experience of applying this
approach to developing more usable digital libraries. This tutorial
assumes no prior knowledge of usability evaluation, and is aimed at all
those involved in the development and deployment of digital libraries
usage and usability assessment: library practices and concerns
This report offers a survey of the methods that are being deployed at leading digital libraries to assess the use and usability of their online collections and services. Focusing on 24 Digital Library Federation member libraries, the study's author, Distinguished DLF Fellow Denise Troll Covey, conducted numerous interviews with library professionals who are engaged in assessment. The report describes the application, strengths, and weaknesses of assessment techniques that include surveys, focus groups, user protocols, and transaction log analysis. Covey's work is also an essential methodological guidebook. For each method that she covers, she is careful to supply a definition, explain why and how libraries use the method, what they do with the results, and what problems they encounter. The report includes an extensive bibliography on more detailed methodological information, and descriptions of assessment instruments that have proved particularly effective
Vector representation of Internet domain names using Word embedding techniques
Word embeddings is a well-known set of techniques widely used in
natural language processing ( NLP ). This thesis explores the use of word
embeddings in a new scenario. A vector space model ( VSM) for Internet
domain names ( DNS) is created by taking core ideas from NLP techniques
and applying them to real anonymized DNS log queries from a large
Internet Service Provider ( ISP) . The main goal is to find semantically
similar domains only using information of DNS queries without any other
knowledge about the content of those domains.
A set of transformations through a detailed preprocessing pipeline
with eight specific steps is defined to move the original problem to a
problem in the NLP field. Once the preprocessing pipeline is applied and
the DNS log files are transformed to a standard text corpus, we show that
state-of-the-art techniques for word embeddings can be successfully
applied in order to build what we called a DNS-VSM (a vector space model
for Internet domain names).
Different word embeddings techniques are evaluated in this work:
Word2Vec (with Skip-Gram and CBOW architectures), App2Vec (with a
CBOW architecture and adding time gaps between DNS queries), and
FastText (which includes sub-word information).
The obtained results are compared using various metrics from Information
Retrieval theory and the quality of the learned vectors is validated with a
third party source, namely, similar sites service offered by Alexa Internet,
Inc2 .
Due to intrinsic characteristics of domain names, we found that FastText is
the best option for building a vector space model for DNS. Furthermore, its
performance (considering the top 3 most similar learned vectors to each
domain) is compared against two baseline methods: Random Guessing
(returning randomly any domain name from the dataset) and Zero Rule
(returning always the same most popular domains), outperforming both of
them considerably.
The results presented in this work can be useful in many
engineering activities, with practical application in many areas. Some
examples include websites recommendations based on similar sites,
competitive analysis, identification of fraudulent or risky sites,
parental-control systems, UX improvements (based on recommendations,
spell correction, etc.), click-stream analysis, representation and clustering
of users navigation profiles, optimization of cache systems in recursive
DNS resolvers (among others).
Finally, as a contribution to the research community a set of vectors
of the DNS-VSM trained on a similar dataset to the one used in this thesis
is released and made available for download through the github page in
[1]. With this we hope that further work and research can be done using
these vectors.La vectorización de palabras es un conjunto de técnicas bien
conocidas y ampliamente usadas en el procesamiento del lenguaje natural
( PLN ). Esta tesis explora el uso de vectorización de palabras en un nuevo
escenario. Un modelo de espacio vectorial ( VSM) para nombres de
dominios de Internet ( DNS ) es creado tomando ideas fundamentales de
PLN, l as cuales son aplicadas a consultas reales anonimizadas de logs de
DNS de un gran proveedor de servicios de Internet ( ISP) . El objetivo
principal es encontrar dominios relacionados semánticamente solamente
usando información de consultas DNS sin ningún otro conocimiento sobre
el contenido de esos dominios.
Un conjunto de transformaciones a través de un detallado pipeline
de preprocesamiento con ocho pasos específicos es definido para llevar el
problema original a un problema en el campo de PLN. Una vez aplicado el
pipeline de preprocesamiento y los logs de DNS son transformados a un
corpus de texto estándar, se muestra que es posible utilizar con éxito
técnicas del estado del arte respecto a vectorización de palabras para
construir lo que denominamos un DNS-VSM (un modelo de espacio
vectorial para nombres de dominio de Internet).
Diferentes técnicas de vectorización de palabras son evaluadas en
este trabajo: Word2Vec (con arquitectura Skip-Gram y CBOW) , App2Vec
(con arquitectura CBOW y agregando intervalos de tiempo entre consultas
DNS ), y FastText (incluyendo información a nivel de sub-palabra).
Los resultados obtenidos se comparan usando varias métricas de la teoría
de Recuperación de Información y la calidad de los vectores aprendidos
es validada por una fuente externa, un servicio para obtener sitios
similares ofrecido por Alexa Internet, Inc .
Debido a características intrínsecas de los nombres de dominio,
encontramos que FastText es la mejor opción para construir un modelo de
espacio vectorial para DNS . Además, su performance es comparada
contra dos métodos de línea base: Random Guessing (devolviendo
cualquier nombre de dominio del dataset de forma aleatoria) y Zero Rule
(devolviendo siempre los mismos dominios más populares), superando a
ambos de manera considerable.
Los resultados presentados en este trabajo pueden ser útiles en
muchas actividades de ingeniería, con aplicación práctica en muchas
áreas. Algunos ejemplos incluyen recomendaciones de sitios web, análisis
competitivo, identificación de sitios riesgosos o fraudulentos, sistemas de
control parental, mejoras de UX (basada en recomendaciones, corrección
ortográfica, etc.), análisis de flujo de clics, representación y clustering de
perfiles de navegación de usuarios, optimización de sistemas de cache en
resolutores de DNS recursivos (entre otros).
Por último, como contribución a la comunidad académica, un
conjunto de vectores del DNS-VSM entrenado sobre un juego de datos
similar al utilizado en esta tesis es liberado y hecho disponible para
descarga a través de la página github en [1]. Con esto esperamos a que
más trabajos e investigaciones puedan realizarse usando estos vectores
Web Data Extraction, Applications and Techniques: A Survey
Web Data Extraction is an important problem that has been studied by means of
different scientific tools and in a broad range of applications. Many
approaches to extracting data from the Web have been designed to solve specific
problems and operate in ad-hoc domains. Other approaches, instead, heavily
reuse techniques and algorithms developed in the field of Information
Extraction.
This survey aims at providing a structured and comprehensive overview of the
literature in the field of Web Data Extraction. We provided a simple
classification framework in which existing Web Data Extraction applications are
grouped into two main classes, namely applications at the Enterprise level and
at the Social Web level. At the Enterprise level, Web Data Extraction
techniques emerge as a key tool to perform data analysis in Business and
Competitive Intelligence systems as well as for business process
re-engineering. At the Social Web level, Web Data Extraction techniques allow
to gather a large amount of structured data continuously generated and
disseminated by Web 2.0, Social Media and Online Social Network users and this
offers unprecedented opportunities to analyze human behavior at a very large
scale. We discuss also the potential of cross-fertilization, i.e., on the
possibility of re-using Web Data Extraction techniques originally designed to
work in a given domain, in other domains.Comment: Knowledge-based System
CHORUS Deliverable 2.2: Second report - identification of multi-disciplinary key issues for gap analysis toward EU multimedia search engines roadmap
After addressing the state-of-the-art during the first year of Chorus and establishing the existing landscape in
multimedia search engines, we have identified and analyzed gaps within European research effort during our second year.
In this period we focused on three directions, notably technological issues, user-centred issues and use-cases and socio-
economic and legal aspects. These were assessed by two central studies: firstly, a concerted vision of functional breakdown
of generic multimedia search engine, and secondly, a representative use-cases descriptions with the related discussion on
requirement for technological challenges. Both studies have been carried out in cooperation and consultation with the
community at large through EC concertation meetings (multimedia search engines cluster), several meetings with our
Think-Tank, presentations in international conferences, and surveys addressed to EU projects coordinators as well as
National initiatives coordinators. Based on the obtained feedback we identified two types of gaps, namely core
technological gaps that involve research challenges, and “enablers”, which are not necessarily technical research
challenges, but have impact on innovation progress. New socio-economic trends are presented as well as emerging legal
challenges
Individual Differences and Instructed Second Language Acquisition: Insights from Intelligent Computer Assisted Language Learning
The present dissertation focuses on the role of cognitive individual difference factors in the acquisition of second language vocabulary in the context of intelligent computer assisted language learning (ICALL). The aim was to examine the association between working memory and declarative memory and the learning of English phrasal verbs in a web-based ICALL-mediated experiment. Following a pretest-posttest design, 127 adult learners of English were assigned to two instructional conditions, namely meaning-focused and form-focused conditions. Learners in both conditions read news texts on the web for about two weeks; learners in the form-focused condition additionally interacted with the texts via selecting multiple-choice options.
The results showed that both working memory and declarative memory were predictive of vocabulary acquisition. However, only the working memory effect was modulated by the instructional context, with the effect being found exclusively in the form-focused condition, and thus suggesting the presence of an aptitude-treatment interaction. Finally, findings also revealed that learning during treatment in the form-focused group was nonlinear, and that paying attention to form and meaning simultaneously impeded global reading comprehension for intermediate, not advanced learners.
From a theoretical perspective, the findings provide evidence to suggest that individual differences in both working memory and declarative memory affect the acquisition of lexical knowledge in ICALL-supported contexts. Methodologically, the current study illustrates the advantages of conducting interdisciplinary work between ICALL and second language acquisition by allowing for the collection of experimental data through a web-based, all-encompassing ICALL system. Overall, the present dissertation represents an initial attempt at characterizing who is likely to benefit from ICALL-based interventions
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