Limited Attention and Centrality in Social Networks

How does one find important or influential people in an online social network? Researchers have proposed a variety of centrality measures to identify individuals that are, for example, often visited by a random walk, infected in an epidemic, or receive many messages from friends. Recent research suggests that a social media users' capacity to respond to an incoming message is constrained by their finite attention, which they divide over all incoming information, i.e., information sent by users they follow. We propose a new measure of centrality --- limited-attention version of Bonacich's Alpha-centrality --- that models the effect of limited attention on epidemic diffusion. The new measure describes a process in which nodes broadcast messages to their out-neighbors, but the neighbors' ability to receive the message depends on the number of in-neighbors they have. We evaluate the proposed measure on real-world online social networks and show that it can better reproduce an empirical influence ranking of users than other popular centrality measures.Comment: in Proceedings of International Conference on Social Intelligence and Technology (SOCIETY2013

A Stochastic Team Formation Approach for Collaborative Mobile Crowdsourcing

Mobile Crowdsourcing (MCS) is the generalized act of outsourcing sensing tasks, traditionally performed by employees or contractors, to a large group of smart-phone users by means of an open call. With the increasing complexity of the crowdsourcing applications, requesters find it essential to harness the power of collaboration among the workers by forming teams of skilled workers satisfying their complex tasks' requirements. This type of MCS is called Collaborative MCS (CMCS). Previous CMCS approaches have mainly focused only on the aspect of team skills maximization. Other team formation studies on social networks (SNs) have only focused on social relationship maximization. In this paper, we present a hybrid approach where requesters are able to hire a team that, not only has the required expertise, but also is socially connected and can accomplish tasks collaboratively. Because team formation in CMCS is proven to be NP-hard, we develop a stochastic algorithm that exploit workers knowledge about their SN neighbors and asks a designated leader to recruit a suitable team. The proposed algorithm is inspired from the optimal stopping strategies and uses the odds-algorithm to compute its output. Experimental results show that, compared to the benchmark exponential optimal solution, the proposed approach reduces computation time and produces reasonable performance results.Comment: This paper is accepted for publication in 2019 31st International Conference on Microelectronics (ICM

A Simple Generative Model of Collective Online Behaviour

Human activities increasingly take place in online environments, providing novel opportunities for relating individual behaviours to population-level outcomes. In this paper, we introduce a simple generative model for the collective behaviour of millions of social networking site users who are deciding between different software applications. Our model incorporates two distinct components: one is associated with recent decisions of users, and the other reflects the cumulative popularity of each application. Importantly, although various combinations of the two mechanisms yield long-time behaviour that is consistent with data, the only models that reproduce the observed temporal dynamics are those that strongly emphasize the recent popularity of applications over their cumulative popularity. This demonstrates---even when using purely observational data without experimental design---that temporal data-driven modelling can effectively distinguish between competing microscopic mechanisms, allowing us to uncover new aspects of collective online behaviour.Comment: Updated, with new figures and Supplementary Informatio

TESTING THE THEORY OF SOCIAL NETWORKING ON EMPOWERMENT OF PEOPLE SPECIALLY WOMEN AT TWO VILLAGES IN BANGLADESH: A FILED INVESTIGATION

This study was an attempt to develop a theory on how social networking facilitates to empower people which were developed by Muhammad Mahboob Ali (2016). The study extensively tries to display a comparative picture regarding different dimensions of empowerment before involving in social networking and after involving in social capital, social business and social investment along with social intelligence ,social enterprises. A concept was tried to build on social networking and then for this applicability of the concept testing along with two co-authors we choose two villages at Khulna District of Bangladesh.   Data were collected through direct interview following an interview schedule during February to April, 2016. The result from the study described those women empowerment is closely related with Social Networking, Social intelligence and social entrepreneurship along with social capital and social investment. Women’s condition are not good before getting involved in social networking and after getting involved in the income of the family had been increasing. After involving in social networking the women started to participate in different income generating activities. Then, they also started to control over income, expenditure, credit and savings. They could then participate in household decision making more than before. It was found that in dimensions the women started to become more empowered than before involving in social networking

Anomaly detection through enhanced sentiment analysis on social media data

Agency for Science, Technology and Research (A*STAR

Estimation of privacy risk through centrality metrics

[EN] Users are not often aware of privacy risks and disclose information in online social networks. They do not consider the audience that will have access to it or the risk that the information continues to spread and may reach an unexpected audience. Moreover, not all users have the same perception of risk. To overcome these issues, we propose a Privacy Risk Score (PRS) that: (1) estimates the reachability of an user¿s sharing action based on the distance between the user and the potential audience; (2) is described in levels to adjust to the risk perception of individuals; (3) does not require the explicit interaction of individuals since it considers information flows; and (4) can be approximated by centrality metrics for scenarios where there is no access to data about information flows. In this case, if there is access to the network structure, the results show that global metrics such as closeness have a high degree of correlation with PRS. Otherwise, local and social centrality metrics based on ego-networks provide a suitable approximation to PRS. The results in real social networks confirm that local and social centrality metrics based on degree perform well in estimating the privacy risk of users.This work is partially supported by the Spanish Government project TIN2014-55206-R and FPI grant BES-2015-074498.Alemany-Bordera, J.; Del Val Noguera, E.; Alberola Oltra, JM.; García-Fornes, A. (2018). Estimation of privacy risk through centrality metrics. Future Generation Computer Systems. 82:63-76. https://doi.org/10.1016/j.future.2017.12.030S63768

End-to-end deep framework for disease named entity recognition using social media data

© 2017 IEEE. A growing interest in the natural language processing methods applied to healthcare applications has been observed in the recent years. In particular, new drug pharmacological properties can be derived patient observations shared in social media forums. Developing approaches designed to automatically retrieve this information is of no low interest for personalized medicine and wide-scale drug tests. The full potential of the effective exploitation of both textual data and published biological data for drug research often goes untapped mostly because of the lack of tools and focused methodologies to curate and integrate the data and transform it into new, experimentally testable hypotheses. Deep learning architectures have shown promising results for a wide range of tasks. In this work, we propose to address a challenging problem by applying modern deep neural networks for disease named entity recognition. An essential step for this task is recognition of disease mentions and medical concept nor-malization, which is highly difficult with simple string matching approaches. We cast the task as an end-to-end problem, solved using two architectures based on recurrent neural networks and pre-trained word embeddings. We show that it is possible to assess the practicability of using social media data to extract representative medical concepts for pharmacovigilance or drug repurposing