51,700 research outputs found

    Emergence of Blind Areas in Information Spreading

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    Recently, contagion-based (disease, information, etc.) spreading on social networks has been extensively studied. In this paper, other than traditional full interaction, we propose a partial interaction based spreading model, considering that the informed individuals would transmit information to only a certain fraction of their neighbors due to the transmission ability in real-world social networks. Simulation results on three representative networks (BA, ER, WS) indicate that the spreading efficiency is highly correlated with the network heterogeneity. In addition, a special phenomenon, namely \emph{Information Blind Areas} where the network is separated by several information-unreachable clusters, will emerge from the spreading process. Furthermore, we also find that the size distribution of such information blind areas obeys power-law-like distribution, which has very similar exponent with that of site percolation. Detailed analyses show that the critical value is decreasing along with the network heterogeneity for the spreading process, which is complete the contrary to that of random selection. Moreover, the critical value in the latter process is also larger that of the former for the same network. Those findings might shed some lights in in-depth understanding the effect of network properties on information spreading

    Homo Socionicus: a Case Study of Simulation Models of Norms

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    This paper describes a survey of normative agent-based social simulation models. These models are examined from the perspective of the foundations of social theory. Agent-based modelling contributes to the research program of methodological individualism. Norms are a central concept in the role theoretic concept of action in the tradition of Durkheim and Parsons. This paper investigates to what extend normative agent-based models are able to capture the role theoretic concept of norms. Three methodological core problems are identified: the question of norm transmission, normative transformation of agents and what kind of analysis the models contribute. It can be shown that initially the models appeared only to address some of these problems rather than all of them simultaneously. More recent developments, however, show progress in that direction. However, the degree of resolution of intra agent processes remains too low for a comprehensive understanding of normative behaviour regulation.Norms, Normative Agent-Based Social Simulation, Role Theory, Methodological Individualism

    Crisis Analytics: Big Data Driven Crisis Response

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    Disasters have long been a scourge for humanity. With the advances in technology (in terms of computing, communications, and the ability to process and analyze big data), our ability to respond to disasters is at an inflection point. There is great optimism that big data tools can be leveraged to process the large amounts of crisis-related data (in the form of user generated data in addition to the traditional humanitarian data) to provide an insight into the fast-changing situation and help drive an effective disaster response. This article introduces the history and the future of big crisis data analytics, along with a discussion on its promise, challenges, and pitfalls

    Predictive coding: A Possible Explanation of Filling-in at the blind spot

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    Filling-in at the blind-spot is a perceptual phenomenon in which the visual system fills the informational void, which arises due to the absence of retinal input corresponding to the optic disc, with surrounding visual attributes. Though there are enough evidence to conclude that some kind of neural computation is involved in filling-in at the blind spot especially in the early visual cortex, the knowledge of the actual computational mechanism is far from complete. We have investigated the bar experiments and the associated filling-in phenomenon in the light of the hierarchical predictive coding framework, where the blind-spot was represented by the absence of early feed-forward connection. We recorded the responses of predictive estimator neurons at the blind-spot region in the V1 area of our three level (LGN-V1-V2) model network. These responses are in agreement with the results of earlier physiological studies and using the generative model we also showed that these response profiles indeed represent the filling-in completion. These demonstrate that predictive coding framework could account for the filling-in phenomena observed in several psychophysical and physiological experiments involving bar stimuli. These results suggest that the filling-in could naturally arise from the computational principle of hierarchical predictive coding (HPC) of natural images.Comment: 23 pages, 9 figure

    Challenges in Complex Systems Science

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    FuturICT foundations are social science, complex systems science, and ICT. The main concerns and challenges in the science of complex systems in the context of FuturICT are laid out in this paper with special emphasis on the Complex Systems route to Social Sciences. This include complex systems having: many heterogeneous interacting parts; multiple scales; complicated transition laws; unexpected or unpredicted emergence; sensitive dependence on initial conditions; path-dependent dynamics; networked hierarchical connectivities; interaction of autonomous agents; self-organisation; non-equilibrium dynamics; combinatorial explosion; adaptivity to changing environments; co-evolving subsystems; ill-defined boundaries; and multilevel dynamics. In this context, science is seen as the process of abstracting the dynamics of systems from data. This presents many challenges including: data gathering by large-scale experiment, participatory sensing and social computation, managing huge distributed dynamic and heterogeneous databases; moving from data to dynamical models, going beyond correlations to cause-effect relationships, understanding the relationship between simple and comprehensive models with appropriate choices of variables, ensemble modeling and data assimilation, modeling systems of systems of systems with many levels between micro and macro; and formulating new approaches to prediction, forecasting, and risk, especially in systems that can reflect on and change their behaviour in response to predictions, and systems whose apparently predictable behaviour is disrupted by apparently unpredictable rare or extreme events. These challenges are part of the FuturICT agenda

    To boldly go:an occam-π mission to engineer emergence

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    Future systems will be too complex to design and implement explicitly. Instead, we will have to learn to engineer complex behaviours indirectly: through the discovery and application of local rules of behaviour, applied to simple process components, from which desired behaviours predictably emerge through dynamic interactions between massive numbers of instances. This paper describes a process-oriented architecture for fine-grained concurrent systems that enables experiments with such indirect engineering. Examples are presented showing the differing complex behaviours that can arise from minor (non-linear) adjustments to low-level parameters, the difficulties in suppressing the emergence of unwanted (bad) behaviour, the unexpected relationships between apparently unrelated physical phenomena (shown up by their separate emergence from the same primordial process swamp) and the ability to explore and engineer completely new physics (such as force fields) by their emergence from low-level process interactions whose mechanisms can only be imagined, but not built, at the current time

    Interaction Between Visual and Phonotactic Orientation During Flight in \u3ci\u3eMagicicada Cassini\u3c/i\u3e (Homoptera: Cicadidae)

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    Visual and phonotactic orientation often occur simultaneously in diurnal cicadas. and these animals generally have their largest sensory elaboration in eyes and hearing organs. Phonotactic orientation occurs principally during flight. Males and females of Magicicada cassini commonly perform low- altitude « 5 m) and short-distance « 15 m) flights in their natural habitat at flight speeds of 3 to 6 m/s. During flight, the long body axis is tilted 10° to Q , head upward. Wing beat frequencies of tethered animals at 24° to 26°C averaged 28.8 Hz. Body temperature in the field for flying individuals aver- aged 4.6°C above ambient. Compound eyes of females possess about 7% more facets than males, and the binocular field of view for both is especially expanded dorsa-frontally, frontally, and fronto-ventrally. The role of vision for phonoresponses, and in flight and landing behavior. was studied in nature by comparing controls with cicadas with eyes partly to completely covered with aluminum paint. Cicadas with their three ocelli covered behaved like controls and exhibited low-altitude and short-distance flights with landings on neighboring shrubs, as did cicadas with only both caudal halves or both dorsal halves of the compound eyes covered. Those with both compound eyes covered completely (with or without additionally covering the three ocelli) flew to higher altitudes and for longer distances. Higher and longer flight courses were also seen in cicadas (A) with only one compound eye covered. which in addition circled during walking and flight toward the side of unrestricted vision, (B) with both frontal or both ventral halves of their compound eyes covered. and (C) with either the binocular or monocular fields of the eyes covered. Thus, the paired fronta-antero-ventral regions of the compound eyes provide visual information for habitat-dependent low-altitude flights and landings. Females with intact compound eyes and ocelli responded to playbacks of just the frequency/intensity sweep at the end of the buzz in calling songs of a male by flying within 1.2 m above the ground and landing on a nylon screen- covered small bush directly above the loudspeaker from distances of 2 to 8 m. mostly from lower vegetation. Males that were blinded, or blinded and deafened, sang less and flew less than normal males. However. they performed all of those behaviors, and all also walked and fed. Periodical cicadas (Magicicada, Tibicininae) are known for synchronized adult emergence and noisy aggregations of millions of individuals of three intermingled species in each brood population (Alexander and Moore 1962). Broods are isolated geographically and chronologically, such that in some years no periodical cicada adults emerge, and most areas of the eastern United States have only one brood population appearing as adults at intervals of either 13 or 17 years. In all Magicicada species, daily flights affect spacing and aggregation of both sexes during feeding, chorusing, mating, and ovipositing. Flights are mediated by both acoustical and visual cues. Each species in these aggregations establishes mating leks. These aggregations continue to mix, every day and unpredictably, during the emergence period. Toward the end of the reproductive season, males die sooner than females, leading to little or no chorusing, and then females disperse progressively further from the lek sites. The cohesive effect of the acoustical cues of chorusing males on these cicada populations is obvious. Both sexes of all six species of periodical cicadas live and feed on shrubs and trees of different species, sizes, and shapes, and females lay eggs in their living twigs. Their niches overlap almost completely, the three species of 13­ year or 17-year cicadas being separated principally by diurnal acoustic behavior leading to aggregation sites that change every day and are seldom exclusive to a single Magicicada species. Adults frequently change location in these complex visual environments by short-distance and low-altitude flights. which we call bush-hopping. These flights are associated with sound communication and reproductive activities and are most commonly observed during bright sunlight and at ambient temperatures above 25°C with little wind (Alexander and Moore 1958,1962; Dunning et al. 1979). Otte (1990) and Toms (1992) discuss the common correlation between hearing and flying in orthop­teroid insects, interactions basically similar to those found in cicadas. The present paper describes the interaction of vision (compound eyes and ocelli) and phonoresponses of males and females of Magicicada cassini (Fisher) in walking, but especially in flight and landing behavior, within a natural habitat

    Marites Culture in the Philippines: An Emergent Online Gossip Phenomenon

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    This research article explores the emergence and characteristics of Marites culture in the Philippines, specifically focusing on its role in shaping social relations and communication during the pandemic and the present. Utilizing literature review approach and sociological perspectives, the study analyzes media reports and online sources to investigate the origins, features, and implications of Marites culture. The research emphasizes the significance of Marites culture as a reflection of broader social and cultural trends in the Philippines, including the increasing importance of online communication and the influence of traditional gossip practices. Moreover, the study examines the potential advantages and disadvantages of Marites culture, such as its ability to disseminate information and shape public opinion, as well as its potential to spread misinformation and trigger social tensions. The findings underscore the necessity for a critical and nuanced understanding of emerging cultural phenomena, considering their historical, social, and cultural contexts and implications
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