TY - JOUR A1 - Pearce, Warren A1 - Özkula, Suay M. A1 - Greene, Amanda K. A1 - Teeling, Lauren A1 - Bansard, Jennifer S. A1 - Omena, Janna Joceli A1 - Rabello, Elaine Teixeira T1 - Visual cross-platform analysis JF - Information, Communication and Society: digital methods to research social media images N2 - Analysis of social media using digital methods is a flourishing approach. However, the relatively easy availability of data collected via platform application programming interfaces has arguably led to the predominance of single-platform research of social media. Such research has also privileged the role of text in social media analysis, as a form of data that is more readily gathered and searchable than images. In this paper, we challenge both of these prevailing forms of social media research by outlining a methodology for visual cross-platform analysis (VCPA), defined as the study of still and moving images across two or more social media platforms. Our argument contains three steps. First, we argue that cross-platform analysis addresses a gap in research methods in that it acknowledges the interplay between a social phenomenon under investigation and the medium within which it is being researched, thus illuminating the different affordances and cultures of web platforms. Second, we build on the literature on multimodal communication and platform vernacular to provide a rationale for incorporating the visual into cross-platform analysis. Third, we reflect on an experimental cross-platform analysis of images within social media posts (n = 471,033) used to communicate climate change to advance different modes of macro- and meso-levels of analysis that are natively visual: image-text networks, image plots and composite images. We conclude by assessing the research pathways opened up by VCPA, delineating potential contributions to empirical research and theory and the potential impact on practitioners of social media communication. KW - research methodology KW - visual analysis KW - social media KW - climate change Y1 - 2018 U6 - https://doi.org/10.1080/1369118X.2018.1486871 SN - 1468-4462 SN - 1369-118X VL - 23 IS - 2 SP - 161 EP - 180 PB - Routledge CY - London ER - TY - JOUR A1 - Shi, Feng A1 - Schirneck, Friedrich Martin A1 - Friedrich, Tobias A1 - Kötzing, Timo A1 - Neumann, Frank T1 - Reoptimization time analysis of evolutionary algorithms on linear functions under dynamic uniform constraints JF - Algorithmica : an international journal in computer science N2 - Rigorous runtime analysis is a major approach towards understanding evolutionary computing techniques, and in this area linear pseudo-Boolean objective functions play a central role. Having an additional linear constraint is then equivalent to the NP-hard Knapsack problem, certain classes thereof have been studied in recent works. In this article, we present a dynamic model of optimizing linear functions under uniform constraints. Starting from an optimal solution with respect to a given constraint bound, we investigate the runtimes that different evolutionary algorithms need to recompute an optimal solution when the constraint bound changes by a certain amount. The classical (1+1) EA and several population-based algorithms are designed for that purpose, and are shown to recompute efficiently. Furthermore, a variant of the (1+(λ,λ))GA for the dynamic optimization problem is studied, whose performance is better when the change of the constraint bound is small. Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-605295 SN - 0178-4617 SN - 1432-0541 VL - 82 IS - 10 SP - 3117 EP - 3123 PB - Springer CY - New York ER - TY - JOUR A1 - Dereudre, David A1 - Houdebert, Pierre T1 - Sharp phase transition for the continuum Widom-Rowlinson model JF - Annales de l'Institut Henri Poincaré. B, Probability and statistics N2 - The Widom-Rowlinson model (or the Area-interaction model) is a Gibbs point process in R-d with the formal Hamiltonian defined as the volume of Ux epsilon omega B1(x), where. is a locally finite configuration of points and B-1(x) denotes the unit closed ball centred at x. The model is also tuned by two other parameters: the activity z > 0 related to the intensity of the process and the inverse temperature beta >= 0 related to the strength of the interaction. In the present paper we investigate the phase transition of the model in the point of view of percolation theory and the liquid-gas transition. First, considering the graph connecting points with distance smaller than 2r > 0, we show that for any beta >= 0, there exists 0 <(similar to a)(zc) (beta, r) < +infinity such that an exponential decay of connectivity at distance n occurs in the subcritical phase (i.e. z <(similar to a)(zc) (beta, r)) and a linear lower bound of the connection at infinity holds in the supercritical case (i.e. z >(similar to a)(zc) (beta, r)). These results are in the spirit of recent works using the theory of randomised tree algorithms (Probab. Theory Related Fields 173 (2019) 479-490, Ann. of Math. 189 (2019) 75-99, Duminil-Copin, Raoufi and Tassion (2018)). Secondly we study a standard liquid-gas phase transition related to the uniqueness/non-uniqueness of Gibbs states depending on the parameters z, beta. Old results (Phys. Rev. Lett. 27 (1971) 1040-1041, J. Chem. Phys. 52 (1970) 1670-1684) claim that a non-uniqueness regime occurs for z = beta large enough and it is conjectured that the uniqueness should hold outside such an half line ( z = beta >= beta(c) > 0). We solve partially this conjecture in any dimension by showing that for beta large enough the non-uniqueness holds if and only if z = beta. We show also that this critical value z = beta corresponds to the percolation threshold (similar to a)(zc) (beta, r) = beta for beta large enough, providing a straight connection between these two notions of phase transition. KW - Gibbs point process KW - DLR equations KW - Boolean model KW - Continuum KW - percolation KW - Random cluster model KW - Fortuin-Kasteleyn representation KW - Randomised tree algorithm KW - OSSS inequality Y1 - 2018 U6 - https://doi.org/10.1214/20-AIHP1082 SN - 0246-0203 SN - 1778-7017 VL - 57 IS - 1 SP - 387 EP - 407 PB - Association des Publications de l'Institut Henri Poincaré CY - Bethesda, Md. ER - TY - JOUR A1 - Brandt, Naemi D. A1 - Becker, Michael A1 - Tetzner, Julia A1 - Brunner, Martin A1 - Kuhl, Poldi A1 - Maaz, Kai T1 - Personality across the lifespan exploring measurement invariance of a short Big Five Inventory from ages 11 to 84 JF - European journal of psychological assessment N2 - Personality is a relevant predictor for important life outcomes across the entire lifespan. Although previous studies have suggested the comparability of the measurement of the Big Five personality traits across adulthood, the generalizability to childhood is largely unknown. The present study investigated the structure of the Big Five personality traits assessed with the Big Five Inventory-SOEP Version (BFI-S; SOEP = Socio-Economic Panel) across a broad age range spanning 11-84 years. We used two samples of N = 1,090 children (52% female, M-age = 11.87) and N = 18,789 adults (53% female, M-age = 51.09), estimating a multigroup CFA analysis across four age groups (late childhood: 11-14 years; early adulthood: 17-30 years; middle adulthood: 31-60 years; late adulthood: 61-84 years). Our results indicated the comparability of the personality trait metric in terms of general factor structure, loading patterns, and the majority of intercepts across all age groups. Therefore, the findings suggest both a reliable assessment of the Big Five personality traits with the BFI-S even in late childhood and a vastly comparable metric across age groups. KW - personality traits KW - measurement invariance KW - ESEM KW - lifespan KW - late KW - childhood Y1 - 2018 U6 - https://doi.org/10.1027/1015-5759/a000490 SN - 1015-5759 SN - 2151-2426 VL - 36 IS - 1 SP - 162 EP - 173 PB - Hogrefe CY - Göttingen ER - TY - JOUR A1 - Muschalla, Beate A1 - Henning, Anne A1 - Haake, Tim Woody A1 - Cornetz, Kathrin A1 - Olbrich, Dieter T1 - Mental health problem or workplace problem or something else BT - what contributes to work perception? JF - Disability and rehabilitation : an international, multidisciplinary journal N2 - Purpose: Work perception is an important predictor for work ability and, therefore, of interest for rehabilitation. Until now it is unclear to which extent different psychological aspects explain work perception. This study investigates in which way workplace problems on the one hand, and mental health and coping on the other hand, contribute to work perception. Methods: A heterogeneous sample of 384 persons in working age with and without mental health problems was recruited. Participants gave self-reports on workplace problems, mental health problems, work-coping, work-anxiety, and work perception. Results: Persons with mental health problems and workplace problems (M + W) perceive the highest degree of work demands, followed by persons with workplace problems but without mental health problems (NM + W). Work-anxiety appeared as the strongest factor explaining perception of high work demands, whereas general mental health problems did not contribute significantly to variance explanation. Conclusions: Persons with specific mental health problems in terms of work-anxiety may be expected to perceive higher work demands. They may be detected when asking for work perception, e.g., within the frame of return-to-work interventions in rehabilitation, or in occupational health settings by mental hazard analysis. KW - work ability KW - work anxiety KW - workplace KW - mental disorders KW - rehabilitation KW - work perception Y1 - 2018 U6 - https://doi.org/10.1080/09638288.2018.1501099 SN - 0963-8288 SN - 1464-5165 VL - 42 IS - 4 SP - 502 EP - 509 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Dvornikov, Yury A1 - Leibman, Marina A1 - Heim, Birgit A1 - Bartsch, Annett A1 - Herzschuh, Ulrike A1 - Skorospekhova, Tatiana A1 - Fedorova, Irina A1 - Khomutov, Artem A1 - Widhalm, Barbara A1 - Gubarkov, Anatoly A1 - Rößler, Sebastian T1 - Terrestrial CDOM in lakes of Yamal Peninsula BT - Connection to lake and lake catchment properties JF - Remote Sensing N2 - In this study, we analyze interactions in lake and lake catchment systems of a continuous permafrost area. We assessed colored dissolved organic matter (CDOM) absorption at 440 nm (a(440)(CDOM)) and absorption slope (S300-500) in lakes using field sampling and optical remote sensing data for an area of 350 km(2) in Central Yamal, Siberia. Applying a CDOM algorithm (ratio of green and red band reflectance) for two high spatial resolution multispectral GeoEye-1 and Worldview-2 satellite images, we were able to extrapolate the a()(CDOM) data from 18 lakes sampled in the field to 356 lakes in the study area (model R-2 = 0.79). Values of a(440)(CDOM) in 356 lakes varied from 0.48 to 8.35 m(-1) with a median of 1.43 m(-1). This a()(CDOM) dataset was used to relate lake CDOM to 17 lake and lake catchment parameters derived from optical and radar remote sensing data and from digital elevation model analysis in order to establish the parameters controlling CDOM in lakes on the Yamal Peninsula. Regression tree model and boosted regression tree analysis showed that the activity of cryogenic processes (thermocirques) in the lake shores and lake water level were the two most important controls, explaining 48.4% and 28.4% of lake CDOM, respectively (R-2 = 0.61). Activation of thermocirques led to a large input of terrestrial organic matter and sediments from catchments and thawed permafrost to lakes (n = 15, mean a(440)(CDOM) = 5.3 m(-1)). Large lakes on the floodplain with a connection to Mordy-Yakha River received more CDOM (n = 7, mean a(440)(CDOM) = 3.8 m(-1)) compared to lakes located on higher terraces. KW - CDOM KW - lakes KW - lake catchments KW - permafrost KW - Yamal KW - remote sensing data Y1 - 2018 U6 - https://doi.org/10.3390/rs10020167 SN - 2072-4292 VL - 10 IS - 2 PB - MDPI CY - Basel ER - TY - JOUR A1 - Goral, Johannah T1 - Lokal Global Digital JF - Kentron : Journal zur Lehrerbildung = Durchstarten Y1 - 2018 SN - 1867-4720 SN - 1867-4747 IS - 32 SP - 36 EP - 39 PB - Universität Potsdam, Zentrum für Lehrerbildung CY - Potsdam ER - TY - JOUR A1 - Faulina, Ariane T1 - Die internationale Bildungsreise JF - Kentron : Journal zur Lehrerbildung = Durchstarten Y1 - 2018 SN - 1867-4720 SN - 1867-4747 IS - 32 SP - 34 EP - 36 PB - Universität Potsdam, Zentrum für Lehrerbildung CY - Potsdam ER - TY - JOUR A1 - Hackel, Manuela T1 - Zeit, Farbe in dein Leben zu bringen JF - Kentron : Journal zur Lehrerbildung = Durchstarten Y1 - 2018 SN - 1867-4720 SN - 1867-4747 IS - 32 SP - 28 EP - 31 PB - Universität Potsdam, Zentrum für Lehrerbildung CY - Potsdam ER - TY - JOUR A1 - Rüdiger, Marie T1 - Weiter geht's BT - das Refugee Teachers Program startet in die zweite Runde JF - Kentron : Journal zur Lehrerbildung = Durchstarten Y1 - 2018 SN - 1867-4720 SN - 1867-4747 IS - 32 SP - 26 EP - 27 PB - Universität Potsdam, Zentrum für Lehrerbildung CY - Potsdam ER -