253 research outputs found

    Die Rechtsstellung des Jugendlichen im spanischen Arbeitsrecht

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    Available from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel A 180268 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

    Grade subjektiver Sicherheit: Verarbeitung und Repräsentation

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    CONTENTS ................................................................................................................. 1 ZUSAMMENFASSUNG ............................................................................................... 4 ABSTRACT .................................................................................................................. 6 LIST OF ORIGINAL RESEARCH ARTICLES ............................................................. 7 1\. GENERAL OVERVIEW ........................................................................................... 8 a. Origins and current state of the experimental investigation of confidence ........... 9 b. Two types of confidence .................................................................................... 11 2\. THE MEASUREMENT OF CONFIDENCE ............................................................ 12 a. Implicit measures ............................................................................................... 12 b. Explicit measures ............................................................................................... 14 3\. PROCESS MODELS OF CONFIDENCE .............................................................. 14 4\. CONFIDENCE AND THE BRAIN .......................................................................... 16 a. Humans .............................................................................................................. 17 b. Animals .............................................................................................................. 18 5\. RESEARCH QUESTIONS ..................................................................................... 19 6\. GENERAL METHODOLOGY ................................................................................ 20 a. Tasks and stimuli ............................................................................................... 20 b. Variables controlled for (quantities held constant) ............................................. 21 c. Subject-specific stimulus calibration ................................................................... 22 d. Measures ........................................................................................................... 22 1\. Behavioral ....................................................................................................... 22 2\. Functional Magnetic Resonance Imaging ...................................................... 23 7\. STUDY SUMMARIES ............................................................................................ 24 a. Study 1 ............................................................................................................... 24 b. Study 2 ............................................................................................................... 26 c. Study 3 ............................................................................................................... 28 8\. GENERAL DISCUSSION ...................................................................................... 30 a. Representation of confidence ............................................................................ 31 1\. Task-independence ........................................................................................ 31 2\. Redundant representation of confidence ........................................................ 32 b. Confidence: epistemic belief or metacognition? ................................................. 33 c. Asking for confidence does not influence decisions ........................................... 34 d. Second-stage processing of both confidence and choice .................................. 36 e. Rating confidence does not require implicit choice ............................................ 37 f. Are confidence ratings decisions? ...................................................................... 37 g. What is the purpose of computing confidence? ................................................. 39 h. Implication of task- independent confidence for subjective probability ............... 39 j. Implications of this dissertation for current process models of confidence and choice ..................................................................................................................... 40 k. Limitations and outlook ....................................................................................... 41 9\. GENERAL CONCLUSION ..................................................................................... 42 REFERENCES .......................................................................................................... 44 EIDESSTATTLICHE ERKLÄRUNG ........................................................................... 50 RESEARCH ARTICLES ............................................................................................ 51Am I really sure? This is a question we ask ourselves practically every day. But when you ask yourself how confident you are, do you ask yourself before or after you make a choice? Most likely you have experienced both and in fact there is good evidence for both pre- and postdecision confidence processing. It remains unclear, however, whether and how these processes differ from each other. More generally, it is an open question how exactly the processing of confidence and choice relate to each other. Finally, it is an open question in which format confidence is represented on the neural level. In the three studies constituting this thesis, I address these issues of representation and processing. In study one, by combining two perceptual decision tasks with functional Magnetic Resonance Imaging (fMRI), I provide neural evidence for a task-independent representation of degrees of subjective certainty (i.e., a neural representation of subjective certainty prior to choice that remains constant across tasks). The results indicate that confidence is represented in an abstract format, i.e. independent of its referent." In study two, I use a perceptual decision task to show that confidence in incorrect trials is higher prior to choice than after choice. At the same time, confidence in correct trials remains unaffected by variation of the response order. This indicates that in contrast to pre decision confidence, post decision confidence is informed by metacognitive error detection. While the former is based on incoming evidence and best viewed as degree of epistemic belief, the latter additionally draws on higher order metacognitive monitoring of the decision process. Therefore, confidence understood as degree of epistemic belief prior to choice is not associated with metacognition, while after choice it is." In study three, I show second stage processing, i.e. continued processing after the first response, of both confidence and choice. In addition, I show that confidence and choice differ in their computational demands, as indicated by longer response times in ratings than decisions. Finally, my results suggest that confidence and choice processing are largely decoupled." Taken together, the present thesis provides novel insights into the representational format of confidence, a conceptual clarification of confidence as degree of belief and an empirical dissociation from related concepts, such as metacognition. Thereby, this thesis adds basic conditions to future theorizing about degrees of belief.Bin ich mir wirklich sicher? Diese Frage stellen wir uns wohl täglich. Aber wenn wir uns fragen, wie sicher wir uns sind, machen wir das bevor oder nachdem wir uns entscheiden? Mit ziemlicher Sicherheit hat man schon beides getan und tatsächlich gibt es empirische Evidenz für die Verarbeitung subjektiver Sicherheit bevor und nachdem wir uns entscheiden. Bislang ist jedoch unklar, ob, und wenn ja, wie, die entsprechenden Prozesse sich voneinander unterscheiden. Darüber hinaus ist auch noch unbekannt, wie genau sich die Berechnung subjektiver Sicherheit und der Entscheidungsprozess zueinander verhalten. Ebenfalls unklar ist, in welchem Format subjektive Sicherheit auf neuronaler Ebene repräsentiert ist. In den drei dieser Arbeit zugrundeliegenden Studien untersuche ich diese Fragen zu Repräsentation und Verarbeitung von Graden subjektiver Sicherheit. In Studie 1 habe ich zwei perzeptuelle Entscheidungsaufgaben mit funktioneller Magnet Resonanz Tomographie (fMRT) kombiniert und gezeigt, dass Grade subjektiver Sicherheit auf neuronaler Ebene in aufgabenunabhängiger Weise repräsentiert sind. Das heißt, ich habe eine neuronale Repräsentation subjektiver Sicherheit gefunden, die über Aufgaben hinweg konstant ist. Dies deutet darauf hin, dass Grade subjektiver Sicherheit in einem abstrakten Format repräsentiert sind, also unabhängig von ihrem Gegenstand." In Studie 2 habe ich mit einer perzeptuellen Entscheidungsaufgabe gezeigt, dass subjektive Sicherheit in Fehlertrials vor Entscheidungen höher ist als nach Entscheidungen. Gleichzeitig bleibt aber subjektive Sicherheit in korrekten Trials unberührt vom Zeitpunkt des Ratings. Dies deutet darauf hin, dass im Gegensatz zu subjektiver Sicherheit vor Entscheidungen, Sicherheit nach Entscheidungen zusätzlich auf metakognitive Fehlerentdeckungsmechanismen zurückgreift. Somit weist subjektive Sicherheit nach Entscheidungen ein metakognitives Element auf, was für subjektive Sicherheit vor Entscheidungen nicht der Fall ist. In Studie 3 zeige ich, dass Verarbeitung auf einer zweiten Ebene, also nach Verarbeitung der ersten Antwort (Sicherheitsrating oder Entscheidung), sowohl für subjektive Sicherheit als auch für Entscheidungen stattfindet. Weiterhin zeige ich, dass die Verarbeitung von subjektiver Sicherheit mehr Rechenaufwand erfordert als die von Entscheidungen. Abschließend legen meine Ergebnisse nahe, dass Sicherheits- und Entscheidungsverarbeitung weitgehend entkoppelt sind. Insgesamt liefert die vorliegende Arbeit neuartige Einsichten in das repräsentationale Format subjektiver Sicherheit, eine konzeptuelle Klärung von subjektiver Sicherheit als Sicherheit in der persönlichen Einschätzung eines Sachverhaltes und eine empirische Abgrenzung zu Nachbarkonzepten wie Metakognition. Dadurch setzt sie Rahmenbedingungen für die weitere Theorienbildung zu Graden subjektiver Sicherheit

    “All humans are cast into battle:” Ephrem the Syrian’s Theology of Spiritual Struggle and Ascetic Heroism

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    Ephrem the Syrian (306–307 CE) is widely celebrated as one of the greatest Christian poets. Previous scholarship has shown that symbolic language is for him a matter of theological necessity. Symbols and metaphors are the idiom of Revelation—they must also be the idiom of theology, of human language about God. If this is true, the study of Ephrem’s use of metaphors should cast into relief theological patterns embedded in his poetry, patterns so subtle and unthematized that they can easily remain undetected (chap. 1).This dissertation examines one specific set of metaphors in the hymns (madrashe) and sermons (memre) of Ephrem: the images of warfare and athletic competition. Agonistic language, it appears, serves Ephrem primarily to describe the ascetic dimension of human existence. The struggle (aguna) into which all humans are cast is the birthright of human freedom, situated between good and evil. A fascinating pattern emerges from Ephrem’s construal of ascetic practices: even as he highlights human agency, he forestalls any potential lapse into voluntarism. Spiritual warfare and ascetic efforts, to Ephrem’s mind, are not a matter of the strong and the elite, but the domain of the weak (chap. 2).Bringing “aguna” as hermeneutical key to biblical stories, often in dialogue with rabbinic traditions, Ephrem highlights such aspects of the patriarchs’ struggles as are applicable to all Christians, showing the extraordinary nature of the seemingly inconspicuous (chaps. 3 and 4). The “Memra on Jonah and the Repentance of Nineveh,” read against the backdrop of ancient epic literature, reveals that Ephrem seeks to create a Christian ideal in which repentance, construed as a battle, is the epitome of heroism (chap. 5).These findings force us to reexamine our understanding of Ephrem as an ascetic author. He has been wrongly characterized as largely uninterested in the concerns of lay life. With his constant emphasis on the heroic nature of ordinary struggles and his insistence on the prominent place of the weak in Christ’s army, Ephrem should instead be seen as an early proponent of an ascetic spirituality for the lay.</p

    IceCube-Gen2: A Vision for the Future of Neutrino Astronomy in Antarctica

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    20 pages, 12 figures. Address correspondence to: E. Blaufuss, F. Halzen, C. Kopper (Changed to add one missing author, no other changes from initial version.)20 pages, 12 figures. Address correspondence to: E. Blaufuss, F. Halzen, C. Kopper (Changed to add one missing author, no other changes from initial version.)20 pages, 12 figures. Address correspondence to: E. Blaufuss, F. Halzen, C. Kopper (Changed to add one missing author, no other changes from initial version.)The recent observation by the IceCube neutrino observatory of an astrophysical flux of neutrinos represents the "first light" in the nascent field of neutrino astronomy. The observed diffuse neutrino flux seems to suggest a much larger level of hadronic activity in the non-thermal universe than previously thought and suggests a rich discovery potential for a larger neutrino observatory. This document presents a vision for an substantial expansion of the current IceCube detector, IceCube-Gen2, including the aim of instrumenting a 10km310\,\mathrm{km}^3 volume of clear glacial ice at the South Pole to deliver substantial increases in the astrophysical neutrino sample for all flavors. A detector of this size would have a rich physics program with the goal to resolve the sources of these astrophysical neutrinos, discover GZK neutrinos, and be a leading observatory in future multi-messenger astronomy programs

    Development of path loss model for 802.11n in large conference rooms

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    In this paper, a path loss (PL) model for 802.11n in large conference rooms is determined, based on PL measurements. The PL can be described accurately by a one-slope model with one standard deviation. PL exponents varying from 1.2 to 1.7 are found. Based on this PL model, the effect of frequency (2.4 vs 5 GHz), configuration (SISO vs MIMO (spatial diversity)), bandwidth (20 vs 40 MHz) and transmit power on number of access points, total power consumption and possible (physical) throughputs is investigated. According to the determined PL model, a higher range (by tuning the transmit power) requires less access points, as well as a lower total power consumption, due to a PL exponent lower than 2

    Searching for eV-scale sterile neutrinos with eight years of atmospheric neutrinos at the IceCube Neutrino Telescope

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    We report in detail on searches for eV-scale sterile neutrinos, in the context of a 3+1 model, using eight years of data from the IceCube Neutrino Telescope. By analyzing the reconstructed energies and zenith angles of 305,735 atmospheric νμ and ν ̄μ events we construct confidence intervals in two analysis spaces: sin2(2θ24) vs Δm412 under the conservative assumption θ34=0; and sin2(2θ24) vs sin2(2θ34) given sufficiently large Δm412 that fast oscillation features are unresolvable. Detailed discussions of the event selection, systematic uncertainties, and fitting procedures are presented. No strong evidence for sterile neutrinos is found, and the best-fit likelihood is consistent with the no sterile neutrino hypothesis with a p value of 8% in the first analysis space and 19% in the second

    IceCube search for dark matter annihilation in nearby galaxies and galaxy clusters

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    We present the results of a first search for self-annihilating dark matter in nearby galaxies and galaxy clusters using a sample of high-energy neutrinos acquired in 339.8 days of live time during 2009/10 with the IceCube neutrino observatory in its 59-string configuration. The targets of interest include the Virgo and Coma galaxy clusters, the Andromeda galaxy, and several dwarf galaxies. We obtain upper limits on the cross section as a function of the weakly interacting massive particle mass between 300 GeV and 100 TeV for the annihilation into bb¯, W+W−, τ+τ−, μ+μ−, and νν¯. A limit derived for the Virgo cluster, when assuming a large effect from subhalos, challenges the weakly interacting massive particle interpretation of a recently observed GeV positron excess in cosmic rays

    Probing the origin of cosmic rays with extremely high energy neutrinos using the IceCube Observatory

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    We have searched for extremely high energy neutrinos using data taken with the IceCube detector between May 2010 and May 2012. Two neutrino induced particle shower events with energies around 1 PeV were observed, as reported previously. In this work, we investigate whether these events could originate from cosmogenic neutrinos produced in the interactions of ultra-high energy cosmic-rays with ambient photons while propagating through intergalactic space. Exploiting IceCube's large exposure for extremely high energy neutrinos and the lack of observed events above 100 PeV, we can rule out the corresponding models at more than 90% confidence level. The model independent quasi-differential 90% CL upper limit, which amounts to E2ϕνe+νμ+ντ=1.2×107E^2 \phi_{\nu_e + \nu_\mu + \nu_\tau} = 1.2 \times 10^{-7} GeV cm2^{-2} s1^{-1} sr1^{-1} at 1 EeV, provides the most stringent constraint in the energy range from 10 PeV to 10 EeV. Our observation disfavors strong cosmological evolution of the highest energy cosmic ray sources such as the Fanaroff-Riley type II class of radio galaxies

    Multiyear search for dark matter annihilations in the Sun with the AMANDA-II and IceCube detectors

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    A search for an excess of muon neutrinos from dark matter annihilations in the Sun has been performed with the AMANDA-II neutrino telescope using data collected in 812 days of live time between 2001 and 2006 and 149 days of live time collected with the AMANDA-II and the 40-string configuration of IceCube during 2008 and early 2009. No excess over the expected atmospheric neutrino background has been observed. We combine these results with the previously published IceCube limits obtained with data taken during 2007 to obtain a total live time of 1065 days. We provide an upper limit at 90% confidence level on the annihilation rate of captured neutralinos in the Sun, as well as the corresponding muon flux limit at the Earth, both as functions of the neutralino mass in the range 50–5000 GeV. We also derive a limit on the neutralino-proton spin-dependent and spin-independent cross section. The limits presented here improve the previous results obtained by the collaboration between a factor of 2 and 5, as well as extending the neutralino masses probed down to 50 GeV. The spin-dependent cross section limits are the most stringent so far for neutralino masses above 200 GeV, and well below direct search results in the mass range from 50 GeV to 5 TeV.R. Abbasi... G. C. Hill... et al. (IceCube Collaboration
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