389 research outputs found

    Is brain activity observable that leads to an evaluation of a probability of 0.5 that is different from 0.5 in binary lottery choices?

    Get PDF
    This paper focuses on the problem of probability weighing in the evaluation of lotteries. According to Prospect Theory a probability of 0.5 has a weight of smaller than 0.5. We conduct an EEG experiment in which we compare the results of the evaluation of binary lotteries by certainty equivalents with the results of the bisection method. The bisection method gives the amount of money that corresponds to the midpoint of the utilities of the two payoffs in a binary lottery as it has been shown previously. In this method probabilities are not evaluated. We analyzed EEG data focused on whether a probability is evaluated or not. Our data show differences between the two methods connected with the attention towards sure monetary payoffs, but they do not show brain activity connected with a devaluation of the probability of 0.5.

    Different methods to define utility functions yield different results and engage different neural processes

    Get PDF
    Although the concept of utility is fundamental to many economic theories, up to now a generally accepted method determining a subject’s utility function is not available. We investigated two methods that are used in economic sciences for describing utility functions by using response-locked event-related potentials in order to assess their neural underpinnings. For defining the certainty equivalent (CE), we used a lottery game with probabilities of 0.5, for identifying the subjects’ utility functions directly a standard bisection task was applied. Although the lottery tasks’ payoffs were only hypothetical, a pronounced negativity was observed resembling the error related negativity (ERN) previously described in action monitoring research, but this occurred only for choices far away from the indifference point between money and lottery. By contrast, the bisection task failed to evoke an ERN irrespective of the responses’ correctness. Based on these findings we are reasoning that only decisions made in the lottery task achieved a level of subjective relevance that activates cognitive-emotional monitoring. In terms of economic sciences, our findings support the view that the bisection method is unaffected by any kind of probability valuation or other parameters related to risk and in combination with the lottery task can, therefore, be used to differentiate between payoff and probability valuation.Utility function; neuroeconomics; error-related negativity; executive functions; cognitive electrophysiology; lottery,bisection

    Modeling J /Psi production and absorption in a microscopic nonequilibrium approach

    Get PDF
    Charmonium production and absorption in heavy ion collisions is studied with the Ultrarelativisitic Quantum Molecular Dynamics model. We compare the scenario of universal and time independent color-octet dissociation cross sections with one of distinct color-singlet J/psi, psi 2 and CHIc states, evolving from small, color transparent configurations to their asymptotic sizes. The measured J/psi production cross sections in pA and AB collisions at SPS energies are consistent with both purely hadronic scenarios. The predicted rapidity dependence of J/psi suppression can be used to discriminate between the two experimentally. The importance of interactions with secondary hadrons and the applicability of thermal reaction kinetics to J/psi absorption are in- vestigated. We discuss the e ect of nuclear stopping and the role of leading hadrons. The dependence of the 2/J/psi ratio on the model assumptions and the possible influence of refeeding processes is also studied

    Dissociation rates of J / psi's with comoving mesons : thermal versus nonequilibrium scenario.

    Get PDF
    We study J/psi dissociation processes in hadronic environments. The validity of a thermal meson gas ansatz is tested by confronting it with an alternative, nonequilibrium scenario. Heavy ion collisions are simulated in the frame- work of the microscopic transport model UrQMD, taking into account the production of charmonium states through hard parton-parton interactions and subsequent rescattering with hadrons. The thermal gas and microscopic transport scenarios are shown to be very dissimilar. Estimates of J/psi survival probabilities based on thermal models of comover interactions in heavy ion collisions are therefore not reliable

    Adapting IT Governance Frameworks using Domain Specific Requirements Methods: Examples from Small & Medium Enterprises and Emergency Management

    Get PDF
    IT Governance methods and frameworks have been applied in most large for-profit organizations since these enterprisesrealize the benefits of IT Governance for their business. However, former research and our own surveys show thatframeworks such as ITIL and COBIT are not very well established in Small and Medium Enterprises (SME) as well as inEmergency Management (EM) organizations. Thus, we investigated what kind of barriers can be the cause for the lowadoption rate. These results built the basis for our Domain Specific Engineering (DSE) approach. The research is based onthe data of two research projects. The first project investigated the utilization of ITSM methods in European SMEs, and thesecond has researched different emergency management organizations. This paper defines similarities and differences of thetwo domain specific solutions, describes the engineering approach, and gives guidelines for further research in otherdomains

    Is brain activity observable that leads to an evaluation of a probability of 0.5 that is different from 0.5 in binary lottery choices?

    Get PDF
    This paper focuses on the problem of probability weighing in the evaluation of lotteries. According to Prospect Theory a probability of 0.5 has a weight of smaller than 0.5. We conduct an EEG experiment in which we compare the results of the evaluation of binary lotteries by certainty equivalents with the results of the bisection method. The bisection method gives the amount of money that corresponds to the midpoint of the utilities of the two payoffs in a binary lottery as it has been shown previously. In this method probabilities are not evaluated. We analyzed EEG data focused on whether a probability is evaluated or not. Our data show differences between the two methods connected with the attention towards sure monetary payoffs, but they do not show brain activity connected with a devaluation of the probability of 0.5

    J/psi suppression in heavy ion collisions - interplay of hard and soft QCD processes

    Get PDF
    We study J/psi suppression in AB collisions assuming that the charmonium states evolve from small, color transparent configurations. Their interaction with nucleons and nonequilibrated, secondary hadrons is simulated us- ing the microscopic model UrQMD. The Drell-Yan lepton pair yield and the J/psi /Drell-Yan ratio are calculated as a function of the neutral transverse en- ergy in Pb+Pb collisions at 160 GeV and found to be in reasonable agreement with existing data
    • …
    corecore