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This article analyzes the dynamics of turnout and the political impact of five cycles of protest, consisting of forty-two mass demonstrations that occurred on Mondays in Leipzig over the period 1989–91. These demonstrations are interpreted as an informational cascade that publicly revealed some of the previously hidden information about the malign nature of the East German communist regime. Once this information became publicly available, the viability of the regime was undermined. The Monday demonstrations subsequently died a slow death as their informational role declined.

AbstractThe classical twin design uses data on the variation of and covariation between monozygotic and dizygotic twins to infer underlying genetic and environmental causes of phenotypic variation in the population. By using data from additional relative classes, such as parents, extended twin family designs more comprehensively describe the causes of phenotypic variation. This article introduces an extension of previous extended twin family models, the Cascade model, which uses information on twins as well as their siblings, spouses, parents, and children to differentiate two genetic and six environmental sources of phenotypic variation. The Cascade also relaxes assumptions regarding mating and cultural transmission that existed in previous extended twin family designs. The estimation of additional parameters and relaxation of assumptions is potentially important, not only because it allows more fine-grained descriptions of the causes of phenotypic variation, but more importantly, because it can reduce the biases in parameter estimates that exist in earlier designs.

Coherent infrared radiation sources are essential for the operability of a wide range of scientific, industrial, military and commercial systems. The importance of the mid-infrared spectral region cannot be understated. Numerous molecules have some vibrational band in this range, allowing for identification of species by means of absorption, emission or some other form of spectroscopy. As such, spectroscopy alone has numerous applications ranging from industrial process control to disease diagnosis utilizing breath analysis. However, despite the discovery of the LASER in the 60s, to this day the amount of coherent sources in this range is limited. It is for this reason that the quantum cascade laser has gained such momentum over the past 23 years.Quantum Cascade LASERS (QCL) are semiconductor LASERS which are based on the principle of bandgap engineering. This incredible technique is a testament to the technological maturity of the semiconductor industry. It has been demonstrated that by having precise control of individual material composition (band gap control), thicknesses on the order of monolayers, and doping levels for each individual layer in a superlattice, we have unprecedented flexibility in designing a LASER or detector in the infrared. And although the technology has matured since it's discovery, there still remain fundamental limitations on device performance. In particular, active region overheating limits QCL performance in a high duty cycle mode of operation.In this dissertation, along with general discussion on the background of the QCL, we propose a solution of where by limiting the growth of the superlattice to a fraction of typical devices, we allow for reduction of the average superlattice temperature under full operational conditions. The consequences of this reduction are explored in theory, experiment and system level applications. ; 2017-05-01 ; Ph.D. ; Sciences, Physics ; Doctoral ; This record was generated from author submitted information.

Intracavity Laser Absorption Spectroscopy (ICLAS) at IR wavelengths offers an opportunity for spectral sensing of low vapor pressure compounds. We report here an ICLAS system design based on a quantum cascade laser (QCL) at THz (69.9 ?m) and IR wavelengths (9.38 and 8.1 ?m) with an open external cavity. The sensitivity of such a system is potentially very high due to extraordinarily long effective optical paths that can be achieved in an active cavity. Sensitivity estimation by numerical solution of the laser rate equations for the THz QCL ICLAS system is determined. Experimental development of the external cavity QCL is demonstrated for the two IR wavelengths, as supported by appearance of fine mode structure in the laser spectrum. The 8.1 ?m wavelength exhibits a dramatic change in the output spectrum caused by the weak intracavity absorption of acetone. Numerical solution of the laser rate equations yields a sensitivity estimation of acetone partial pressure of 165 mTorr corresponding to ~ 200 ppm. The system is also found sensitive to the humidity in the laboratory air with an absorption coefficient of just 3 x 10-7 cm-1 indicating a sensitivity of 111 ppm. Reported also is the design of a compact integrated data acquisition and control system. Potential applications include military and commercial sensing for threat compounds such as explosives, chemical gases, biological aerosols, drugs, banned or invasive organisms, bio-medical breath analysis, and terrestrial or planetary atmospheric science. ; 2011-12-01 ; Ph.D. ; Sciences, Physics ; Doctoral ; This record was generated from author submitted information.

AbstractDigitally networked and new, unconventional activities allow citizens to participate politically in activities that are low in the effort and risks they bear. At the same time, low-effort types of participation are more loosely connected to democratic political systems, thereby challenging established modes of political decision-making. This can set in motion two competing dynamics: While some citizens move closer to the political system in their activities (upstream effects), others engage in political activities more distant from it (downstream effects). This study investigates non-electoral participation trajectories and tests intra-individual change in political participation types over time, exploring whether such dynamics depend on citizens' exposure to political information. Utilizing a three-wave panel survey (n = 3490) and random intercept cross-lagged panel models with SEM, we find more evidence for downstream effects but detect overall diverse participation trajectories over time and a potentially crucial role of elections for non-electoral participation trajectories.

Interstate 90 over the Cascades is a significant barrier to over 250 species of wildlife, including cougar, elk, deer, mustelids (otters, fishers, badgers, etc.), amphibians, and reptiles. In the vicinity of Snoqualmie Pass, urban development to the west and agriculture and resort development on the east has shrunk the forest connecting the north and south Cascades to less than 64.6 kilometers wide. The Washington State Department of Transportation (WSDOT) is proposing to expand a 24.15-kilometer stretch of Interstate 90 just east of Snoqualmie Pass through a particularly critical zone for north-south wildlife corridors. Absent effective wildlife-crossing structures, the expansion would worsen the barrier by increasing roadkill and further isolating populations, thus inhibiting genetic exchange. However, the state has made ecological connectivity a project goal, along with increasing capacity, straightening curves, and repaving. The I-90 Wildlife Bridges Coalition has been working with WSDOT, other public officials, transportation interests, and the public to promote high-quality wildlife-crossing structures. Such structures can also improve safety for motorists by reducing collisions that are sometimes fatal to humans, as well as wildlife. Good data is available to inform where to build crossing structures. WSDOT and the US Forest Service collaborated on a study entitled I-90 Snoqualmie Pass Wildlife Habitat Linkage Assessment (Singleton and Lehmkuhl 2000) that used tracking and road-kill counts to map existing crossing activity. Additional relevant information comes from analysis leading to the Snoqualmie Pass Adaptive Management Area Plan and I-90 Land Exchange (US Forest Service, 1997 and 1999) and Washington State Dept. of Fish and Wildlife studies of cougar movements using radio collars. Recent land acquisitions and national forest-management changes have dramatically improved the outlook for habitat quality near the project. In recent years, purchases, donations, and exchanges have brought more than 50,000 acres of land valued at $200 million into public ownership and protection. The Forest Service is committing to additional habitat restoration, such as road removal. Two of the distinguishing features of the I-90 project are the prevalence of wetlands associated with the Yakima River and the variation in habitat as precipitation and elevation decline from west to east. A variety of structure types—from extended vehicle bridges, to box culverts, to overpasses specifically for wildlife—is required to allow both hydrological connectivity and connections for a diverse array of species. Preferred habitat conditions and existing movement patterns are balanced with site-specific design considerations, including cost, to establish a range of possible solutions to be presented in a draft environmental-impact statement due in spring 2005. Given the intense competition for transportation funds, particularly big-ticket projects near urban areas, the I-90 Snoqualmie Pass East project will need broad-based support to obtain funding. To overcome the environmental community's general opposition to expanded freeways, the project will need to provide a high level of wildlife connectivity. Project proponents will also need to navigate anti-tax politics by joining in a diverse coalition of agencies, conservation groups, and shipping interests. The recent partnership to acquire habitat north and south of the project points the way. The coalition has grown out of a history of grassroots activism and collaboration around the Central Cascades region. Citizen involvement has played a critical role in the management policies of this area. The I-90 project will be a greater success due to the high level of attention and input received from the public. Public involvement will have peaked in the spring of 2005 with the release of the Draft Environmental Impact Statement followed by five public comment hearings throughout Washington State. This input will be considered throughout the summer of 2005 and (hopefully) brought to a successful completion in the fall/winter of the same year.

chapter 1 Why study information economics? -- chapter 2 How to use this book -- part PART I Information as an economic good -- chapter 3 What is information? -- chapter 4 The value of information -- chapter 5 The optimal amount of information -- chapter 6 The production of information -- part PART II How the market aggregates information -- chapter 7 From information to prices -- chapter 8 A Introduction -- chapter 9 Coordination problems -- chapter 10 Learning and cascades -- chapter 11 The macroeconomics of information -- part PART III Asymmetric information -- chapter 12 The winner's curse -- chapter 13 Information and selection -- chapter 14 Optimal contracts -- chapter 15 The revelation principle -- chapter 16 A Introduction -- part PART IV The economics of self-knowledge -- chapter 17 Me, Myself, and I.

Despite the intensive study of the viral spread of fake news in political echo chambers (ECs) on social networking services (SNSs), little is known regarding the underlying structure of the daily information spread in these ECs. Moreover, the effect of SNSs on opinion polarisation is still unclear in terms of pluralistic information access or selective exposure to opinions in an SNS. In this study, we confirmed the steady, highly independent nature of left- and right-leaning ECs, both of which are composed of approximately 250,000 users, from a year-long reply/retweet network of 42 million Japanese Twitter users. We found that both communities have similarly efficient information spreading networks with densely connected and core-periphery structures. Core nodes resonate in the early stages of information cascades, and unilaterally transmit information to peripheral nodes. Each EC has resonant core users who amplify and steadily spread information to a quarter of a million users. In addition, we confirmed the existence of extremely aggressive users of ECs who co-reply/retweet each other. The connection between these users and top influencers suggests that the extreme opinions of the former group affect the entire community through the top influencers.

Intro -- Preface and Acknowledgments -- Contents -- About the Authors -- Chapter 1: Characterising Social Machines -- Introduction -- What Is a Social Machine? The Machine Metaphor -- Ten Aspects of Machines -- Mechanistic Explanation -- Building Blocks of Social Machines -- Heterogeneous Human-Computer Networks -- Social Computing -- Communication -- Communication and Engagement Within Social Machines -- Communication as Annotation -- Platforms and Communities -- Social Machines and Their Ecosystems -- From Network to Activity -- Ethical Concepts -- The Dark Side -- Some Examples of Social Machines -- Wikipedia -- Citizen Science -- Healthcare -- Pokémon Go! -- Classifying Social Machines -- Social Machines and Related Paradigms -- Defining Social Machines -- Analysing and Engineering: A Social Machine Lens -- Chapter 2: Theory -- Introduction -- Social Machines as Social -- Narratives -- Prosopography -- Example Narrative 1: Retweeting -- Example Narrative 2: Green Peas in 12 Moments -- Wayfaring -- Transcendental Information Cascades -- Example Application of Transcendental Information Cascades 1: Citizen Science -- Example Application of Transcendental Information Cascades 2: Wikipedia -- Decomposing Reflexivity -- Social Computing and Diversity: Mandevillian Intelligence -- Social Machines as Machines -- The Lightweight Social Calculus -- Shadow Institutions -- Sociograms -- Modelling Coordination and Quality Constraints -- Data -- Annotation -- Annotations and Data -- Annotations vs. Data? -- Provenance -- Use Cases for Provenance in Social Machines -- Functional Use Cases -- Audit Use Cases -- Privacy and Security Use Cases -- Administrative Use Cases -- Provenance Methodology -- Standardisation -- Templates -- Composition -- Summarisation -- Provenance Network Analytics -- Deriving Provenance for Social Computation.

Abstract
Recent years have witnessed a swelling rise of hateful and abusive content over online social networks. While detection and moderation of hate speech have been the early go-to countermeasures, the solution requires a deeper exploration of the dynamics of hate generation and propagation. We analyze more than 32 million posts from over 6.8 million users across three popular online social networks to investigate the interrelations between hateful behavior, information dissemination, and polarized organization mediated by echo chambers. We find that hatemongers play a more crucial role in governing the spread of information compared to singled-out hateful content. This observation holds for both the growth of information cascades as well as the conglomeration of hateful actors. Dissection of the core-wise distribution of these networks points towards the fact that hateful users acquire a more well-connected position in the social network and often flock together to build up information cascades. We observe that this cohesion is far from mere organized behavior; instead, in these networks, hatemongers dominate the echo chambers—groups of users actively align themselves to specific ideological positions. The observed dominance of hateful users to inflate information cascades is primarily via user interactions amplified within these echo chambers. We conclude our study with a cautionary note that popularity-based recommendation of content is susceptible to be exploited by hatemongers given their potential to escalate content popularity via echo-chambered interactions.

"Rational Choice Theory in Political Decision Making" published on by Oxford University Press.