77 research outputs found
Comparing and Combining Sentiment Analysis Methods
Several messages express opinions about events, products, and services,
political views or even their author's emotional state and mood. Sentiment
analysis has been used in several applications including analysis of the
repercussions of events in social networks, analysis of opinions about products
and services, and simply to better understand aspects of social communication
in Online Social Networks (OSNs). There are multiple methods for measuring
sentiments, including lexical-based approaches and supervised machine learning
methods. Despite the wide use and popularity of some methods, it is unclear
which method is better for identifying the polarity (i.e., positive or
negative) of a message as the current literature does not provide a method of
comparison among existing methods. Such a comparison is crucial for
understanding the potential limitations, advantages, and disadvantages of
popular methods in analyzing the content of OSNs messages. Our study aims at
filling this gap by presenting comparisons of eight popular sentiment analysis
methods in terms of coverage (i.e., the fraction of messages whose sentiment is
identified) and agreement (i.e., the fraction of identified sentiments that are
in tune with ground truth). We develop a new method that combines existing
approaches, providing the best coverage results and competitive agreement. We
also present a free Web service called iFeel, which provides an open API for
accessing and comparing results across different sentiment methods for a given
text.Comment: Proceedings of the first ACM conference on Online social networks
(2013) 27-3
XYZ Privacy
Future autonomous vehicles will generate, collect, aggregate and consume
significant volumes of data as key gateway devices in emerging Internet of
Things scenarios. While vehicles are widely accepted as one of the most
challenging mobility contexts in which to achieve effective data
communications, less attention has been paid to the privacy of data emerging
from these vehicles. The quality and usability of such privatized data will lie
at the heart of future safe and efficient transportation solutions.
In this paper, we present the XYZ Privacy mechanism. XYZ Privacy is to our
knowledge the first such mechanism that enables data creators to submit
multiple contradictory responses to a query, whilst preserving utility measured
as the absolute error from the actual original data. The functionalities are
achieved in both a scalable and secure fashion. For instance, individual
location data can be obfuscated while preserving utility, thereby enabling the
scheme to transparently integrate with existing systems (e.g. Waze). A new
cryptographic primitive Function Secret Sharing is used to achieve
non-attributable writes and we show an order of magnitude improvement from the
default implementation.Comment: arXiv admin note: text overlap with arXiv:1708.0188
Sentiment Lexicon Adaptation with Context and Semantics for the Social Web
Sentiment analysis over social streams offers governments and organisations a fast and effective way to monitor the publics' feelings towards policies, brands, business, etc. General purpose sentiment lexicons have been used to compute sentiment from social streams, since they are simple and effective. They calculate the overall sentiment of texts by using a general collection of words, with predetermined sentiment orientation and strength. However, words' sentiment often vary with the contexts in which they appear, and new words might be encountered that are not covered by the lexicon, particularly in social media environments where content emerges and changes rapidly and constantly. In this paper, we propose a lexicon adaptation approach that uses contextual as well as semantic information extracted from DBPedia to update the words' weighted sentiment orientations and to add new words to the lexicon. We evaluate our approach on three different Twitter datasets, and show that enriching the lexicon with contextual and semantic information improves sentiment computation by 3.4% in average accuracy, and by 2.8% in average F1 measure
Human diffusion and city influence
International audienceCities are characterized by concentrating population, economic activity and services. However, not all cities are equal and a natural hierarchy at local, regional or global scales spontaneously emerges. In this work, we introduce a method to quantify city influence using geolocated tweets to characterize human mobility. Rome and Paris appear consistently as the cities attracting most diverse visitors. The ratio between locals and non-local visitors turns out to be fundamental for a city to truly be global. Focusing only on urban residents' mobility flows, a city to city network can be constructed. This network allows us to analyze centrality measures at different scales. New York and London play a predominant role at the global scale, while urban rankings suffer substantial changes if the focus is set at a regional level
Teachers and Digital Literacies: Mixed-Methods Investigation into 1:1 Technology-Enhanced Learning Environments
Despite the bustling technological landscape in which we live and learn, technology is still limited in its integration within classrooms. The current drive in education to promote 21st-century skills and digital literacies appears to remain relatively idle for a variety of reasons. This mixed-methods study examines the impact 1:1 technology has on digital literacies and the barriers faced by teachers with its incorporation into secondary classrooms. It explores the extent to which instructors within 1:1 environments perceive their technology integration and investigates how this indirectly impacts the acquisition of digital literacies within the classroom. By gaining more insight into how technology and digital literacy skills are integrated into 1:1 classrooms, we may gain insight into current integration practices as well as barriers to implementation, furthering literature in this area. Moreover, this research may enable educational systems to effectively align beliefs, research, and practice to support teachers in meeting newly adopted technologies and digital literacy standards
Collateral damage of Facebook Apps: an enhanced privacy scoring model
Establishing friendship relationships on Facebook often entails information sharing which is based on the social trust and implicit contract between users and their friends. In this context, Facebook offers applications (Apps) developed by third-party application providers (AppPs), which may grant access to users\u27 personal data via Apps installed by their friends. Such access takes place outside the circle of social trust with the user not being aware whether a friend has installed an App collecting her data. In some cases, one or more AppPs may cluster several Apps and thus gain access to a collection of personal data. As a consequence privacy risks emerge. Previous research has mentioned the need to quantify privacy risks on Online Social Networks (OSNs). Nevertheless, most of the existing works do not focus on the personal data disclosure via Apps. Moreover, the problem of personal data clustering from AppPs has not been studied. In this work, we perform a general analysis of the privacy threats stemming from the personal data requested by Apps installed by the user’s friends from a technical and legal point of view. In order to assist users, we propose a model and a privacy scoring formula to calculate the amount of personal data that may be exposed to AppPs. Moreover, we propose algorithms that based on clustering, computes the visibility of each personal data to the AppPs
Privacy Intelligence: A Survey on Image Sharing on Online Social Networks
Image sharing on online social networks (OSNs) has become an indispensable
part of daily social activities, but it has also led to an increased risk of
privacy invasion. The recent image leaks from popular OSN services and the
abuse of personal photos using advanced algorithms (e.g. DeepFake) have
prompted the public to rethink individual privacy needs when sharing images on
OSNs. However, OSN image sharing itself is relatively complicated, and systems
currently in place to manage privacy in practice are labor-intensive yet fail
to provide personalized, accurate and flexible privacy protection. As a result,
an more intelligent environment for privacy-friendly OSN image sharing is in
demand. To fill the gap, we contribute a systematic survey of 'privacy
intelligence' solutions that target modern privacy issues related to OSN image
sharing. Specifically, we present a high-level analysis framework based on the
entire lifecycle of OSN image sharing to address the various privacy issues and
solutions facing this interdisciplinary field. The framework is divided into
three main stages: local management, online management and social experience.
At each stage, we identify typical sharing-related user behaviors, the privacy
issues generated by those behaviors, and review representative intelligent
solutions. The resulting analysis describes an intelligent privacy-enhancing
chain for closed-loop privacy management. We also discuss the challenges and
future directions existing at each stage, as well as in publicly available
datasets.Comment: 32 pages, 9 figures. Under revie
- …