Emotional reactions to real-world events in social networks

A convergence of emotions among people in social networks is potentially resulted by the occurrence of an unprecedented event in real world. E.g., a majority of bloggers would react angrily at the September 11 terrorist attacks. Based on this observation, we introduce a sentiment index, computed from the current mood tags in a collection of blog posts utilizing an affective lexicon, potentially revealing subtle events discussed in the blogosphere. We then develop a method for extracting events based on this index and its distribution. Our second contribution is establishment of a new bursty structure in text streams termed a sentiment burst. We employ a stochastic model to detect bursty periods of moods and the events associated. Our results on a dataset of more than 12 million mood-tagged blog posts over a 4-year period have shown that our sentiment-based bursty events are indeed meaningful, in several ways.

Least squares asymptotics in spurious and cointegrated panel regressions with common and idiosyncratic stochastic trends

This article makes an analytical study of the effects of the presence of both common and idiosyncratic stochastic trends on the pooled least squares estimator. The results suggest that the usual result of asymptotic normality depends critically on the absence of the common stochastic trend.

Event extraction using behaviors of sentiment signals and burst structure in social media

Significant world events often cause the behavioral convergence of the expression of shared sentiment. This paper examines the use of the blogosphere as a framework to study user psychological behaviors, using their sentiment responses as a form of ‘sensor’ to infer real-world events of importance automatically. We formulate a novel temporal sentiment index function using quantitative measure of the valence value of bearing words in blog posts in which the set of affective bearing words is inspired from psychological research in emotion structure. The annual local minimum and maximum of the proposed sentiment signal function are utilized to extract significant events of the year and corresponding blog posts are further analyzed using topic modeling tools to understand their content. The paper then examines the correlation of topics discovered in relation to world news events reported by the mainstream news service provider, Cable News Network, and by using the Google search engine. Next, aiming at understanding sentiment at a finer granularity over time, we propose a stochastic burst detection model, extended from the work of Kleinberg, to work incrementally with stream data. The proposed model is then used to extract sentimental bursts occurring within a specific mood label (for example, a burst of observing ‘shocked’). The blog posts at those time indices are analyzed to extract topics, and these are compared to real-world news events. Our comprehensive set of experiments conducted on a large-scale set of 12 million posts from Livejournal shows that the proposed sentiment index function coincides well with significant world events while bursts in sentiment allow us to locate finer-grain external world events.

The impact of divergent historical and cultural factors on convergence in global communication practice

Communication practice is increasingly converging around globally consistent approaches and techniques shaped by both globalisation and globalising communications technologies. However, this paper argues, national and regional practice histories and cultural characteristics have shaped, and continue to shape, practice in individual markets. The paper analyses the extent of that these divergent histories and cultures have shaped the structure and practices of the public relations industry in Australia and other countries. The paper challenges the common assumptions about public relations development and industry practice having developed from a predominantly US-based model progressively disseminated globally. It traces the history of public relations in Australia, counter-pointing its distinctive origins, to the US-origin thesis. It also examines the impact of demography and diverse national culture on industry shape and practice, comparing the Australian industry to that of other industries around the world. It uses mini-case studies of campaigns in specific countries to assess the extent to which they are culturally-bound by historical and cultural differences and the extent to which they are capable of being transferred or adapted to individual markets. For instance, assumptions about globally-consistent brand identities are contradicted by McDonalds’ branding practices in markets such as Canada and Japan. The paper also discusses how emerging market PR industries are being shaped by distinctive and divergent cultures and development paths and may create new structural and practice models as the emerging economies becoming dominant internationally. The authors suggest that history and cultural diversity continue, and will continue to, shape national and regional practices.

Contests with the probability of a draw : a stochastic foundation

This article proposes a stochastic foundation for the contest success function (CSF for short) with a richer structure on the set of possible outcomes of the contest. Specifically, the analysis allows for the possibility of a draw, so that no contestant can claim a victory over all other players. Under plausible conditions, this article not only discovers new functional forms of CSFs, but also shows the newly derived CSFs have very different properties in equilibrium to those of conventional CSFs. For example, in contrast to the CSFs discussed in the contest literature, which always generate a unique pure strategy Nash equilibrium, the newly discovered CSFs admit the possibility of multiple equilibria.

Web 2.0 : an argument against convergence

Web 2.0 has been a dominant concept in recent discussion and development of Internet applications, businesses and uses. Dating from 2004, the term Web 2.0 is variously understood as new forms of website development and delivery technology, changing uses of the Internet to emphasise sociability over consumption, new understandings of the possible financial exploitation of the web, and more broadly, a new way of thinking about the Internet as a whole. However, Web 2.0 is, conceptually, both more and less than these various understandings and we can only grasp why it has become such a key term in contemporary usage by appreciating two key discursive foundations for this term. Firstly, much Web 2.0 thinking is a re-expression of long-held ideas about the Internet and the web. Secondly, at the particular time when Web 2.0 was made popular, net technology policy makers and financial analysts were primarily enthused by the possibilities of broadband networks for improved and more profitable versions of the well-established businesses of telephony and audio-visual entertainment, and had to some extent consigned novel, web-based services to a lesser role, following the dot.com crash. Thus, as I argue in this paper, Web 2.0 can be understood as a key intervention, from within the dot.com / new media business sector, recovering from the crash, that re-asserts the equal legitimacy of the use of networked computing, over high-speed lines, for computing-oriented activities, and not just video on demand and voice over IP. In short, in the first years of this century, discussions about the future of the Internet had become dominated by arguments for increased broadband access, substantially concerned with providing more traditional video and voice services in new ways. The World Wide Web was seen as relatively unimportant for this purpose, even though it was part of the so-called 'triple play' of voice and data services. At this time, first in the hands of Tim O'Reilly and then from others who took up his position, Web 2.0 became a catchy simple term under which to mount a campaign for the renaissance of the World Wide Web as a quite distinct, yet equally important, form of media and communications. So, Web 2.0 provides evidence that, while there is a convergence of all forms of media and communications towards similar data traffic over the Internet, there remain diverging views over the nature, control and use of the Internet, views that express the degree to which corporate players imagine themselves to be 'media', 'telephony' or 'computing' in primary orientation.

Stochastic models of road geometry and wind condition for vehicle energy management and control

Modeling and simulation is commonly used to improve vehicle performance, to optimize vehicle system design, and to reduce vehicle development time. Vehicle performances can be affected by environmental conditions and driver behavior factors, which are often uncertain and immeasurable. To incorporate the role of environmental conditions in the modeling and simulation of vehicle systems, both real and artificial data are used. Often, real data are unavailable or inadequate for extensive investigations. Hence, it is important to be able to construct artificial environmental data whose characteristics resemble those of the real data for modeling and simulation purposes. However, to produce credible vehicle simulation results, the simulated environment must be realistic and validated using accepted practices. This paper proposes a stochastic model that is capable of creating artificial environmental factors such as road geometry and wind conditions. In addition, road geometric design principles are employed to modify the created road data, making it consistent with the real-road geometry. Two sets of real-road geometry and wind condition data are employed to propose probability models. To justify the distribution goodness of fit, Pearson's chi-square and correlation statistics have been used. Finally, the stochastic models of road geometry and wind conditions (SMRWs) are developed to produce realistic road and wind data. SMRW can be used to predict vehicle performance, energy management, and control strategies over multiple driving cycles and to assist in developing fuel-efficient vehicles.