Non-Parametric Maximum Likelihood Density Estimation and Simulation-Based Minimum Distance Estimators

Indirect inference estimators (i.e., simulation-based minimum distance estimators) in a parametric model that are based on auxiliary non-parametric maximum likelihood density estimators are shown to be asymptotically normal. If the parametric model is correctly specified, it is furthermore shown that the asymptotic variance-covariance matrix equals the inverse of the Fisher-information matrix. These results are based on uniform-in-parameters convergence rates and a uniform-in-parameters Donsker-type theorem for non-parametric maximum likelihood density estimators.Comment: minor corrections, some discussion added, some material remove

Non-Parametric Maximum Likelihood Density Estimation and Simulation-Based Minimum Distance Estimators

Indirect inference estimators (i.e., simulation-based minimum distance estimators) in a parametric model that are based on auxiliary non-parametric maximum likelihood density estimators are shown to be asymptotically normal. If the parametric model is correctly specified, it is furthermore shown that the asymptotic variance-covariance matrix equals the Cramér-Rao bound. These results are based on uniform-in-parameters convergence rates and a uniform-in-parameters Donsker-type theorem for non-parametric maximum likelihood density estimators.Indirect inference, simulation-based minimum distance estimation, non-parametric maximum likelihood, density estimation, efficiency

Longitudinal Response of Confined Semiflexible Polymers

The longitudinal response of single semiflexible polymers to sudden changes in externally applied forces is known to be controlled by the propagation and relaxation of backbone tension. Under many experimental circumstances, realized, e.g., in nano-fluidic devices or in polymeric networks or solutions, these polymers are effectively confined in a channel- or tube-like geometry. By means of heuristic scaling laws and rigorous analytical theory, we analyze the tension dynamics of confined semiflexible polymers for various generic experimental setups. It turns out that in contrast to the well-known linear response, the influence of confinement on the non-linear dynamics can largely be described as that of an effective prestress. We also study the free relaxation of an initially confined chain, finding a surprising superlinear t^(9/8) growth law for the change in end-to-end distance at short times.Comment: 18 pages, 1 figur

COVID-19: Guaranteed Loans and Zombie Firms

Based on the ZHAW Managers Survey (7-13 April 2020) we evaluate firm reactions towards the COVID-19 crisis. We find that the Swiss economic lockdown measures successfully froze the economy, i.e., firms show very little pro-active reactions towards the crisis, but drastically decrease their business activities. The firms in the survey report that the decline in foreign demand is the single most important reasons for their deteriorating business situation. The only significant pro-active reactions to mitigate the crisis are increased digitalization efforts. These efforts are expected to have a long-lasting impact on firms' performance due to a selection effect, i.e., firms with more positive experience of digitialization will maintain their higher levels of digitalization even after the crisis. In general we find that firms that faced a more difficult business situation before the crisis are affected more severely during the crisis. Moreover, we investigate the impact of the Swiss federal loan program (Bundeshilfe) on the business activities of Swiss firms. Specifically, we focus on the take up of firms and its interaction with the perceived business situation before and during the COVID-19 crisis. To this end, we develop a stylized theoretical model of financially constrained heterogeneous firms. We find that policy makers face a trade-off between immediate higher unemployment rates and long-term higher public spending. The former arises from a combination of a too strong economic impact of the COVID-19 lockdown and too low levels of loans provided by the government to financially distressed firms. Nevertheless, providing (too) high levels of loans to firms might create zombie firms that are going to default on their debt in the future leading to an increase in public spending

Reservoir Engineering for Classical Nonlinear Fields

Reservoir engineering has become a prominent tool to control quantum systems. Recently, there have been first experiments applying it to many-body systems, especially with a view to engineer particle-conserving dissipation for quantum simulations using bosons. In this work, we explore the dissipative dynamics of these systems in the classical limit. We derive a general equation of motion capturing the effective nonlinear dissipation introduced by the bath and apply it to the special case of a Bose-Hubbard model, where it leads to an unconventional type of dissipative nonlinear Schr\"odinger equation. Building on that, we study the dynamics of one and two solitons in such a dissipative classical field theory.Comment: 14 pages, 6 figure

Predicting Intentions to Read Suicide Awareness Stories: The Role of Depression and Characteristics of the Suicidal Role Model

Background: Research on factors that influence the intention to read suicide awareness material is lacking. Aims: To identify how social and state similarities between the featured protagonist of a suicide awareness story and the audience impact on the intent to read similar stories. Method: Laboratory experiment with n = 104 students. Participants were randomly assigned to study groups. In the first group, the role model provided his personal story of crisis and was a student. In the second group, the content was identical but the model was socially dissimilar. The third group read about a topic unrelated to suicide. Depression, identification, and exposure intent were measured after the experiment. Conditional process analysis was carried out. Results: In the group featuring a once-suicidal role model with high social similarity, depression in the audience increased the intention to read similar material in the future via identification with the role model; 82% of individuals wanted to read similar material in the future, but only 50% wanted to do so in the group featuring a dissimilar person. Conclusion: Exposure intention increases via identification when role model and audience characteristics align regarding social traits and the experience of depression. These factors are relevant when developing campaigns targeting individuals with stories of recovery

BREAKING DOWN THE BLOCKCHAIN HYPE – TOWARDS A BLOCKCHAIN MARKET ENGINEERING APPROACH

The blockchain has reached the tip of a global hype across a variety of industries. The potential of this technology, inter alia building the fundament of Bitcoin, is assumed to be immense and disruptive – particularly for the financial industry. FinTech start-ups as well as established players however are just about to explore the true potential of blockchain technology as the fundament of (financial) markets. Before this backdrop, Information Systems research is making valuable contributions to the field by integrating the technical view on blockchain with interdisciplinary research approaches. Our contribution to the growing body of Information Systems literature in the context of the blockchain is twofold: First, we conduct a comprehensive literature review of the most relevant and recent IS research on blockchain. Second, based on the findings of our review, we build on existing research and propose a Blockchain Market Engineering Framework, which can support researchers as well as practitioners in analyzing and designing the elements of blockchain-based markets on an individual and global level. In addition, we go beyond a purely analytical perspective and provide a toolbox to support the active construction of blockchain-based ecosystems and infrastructures. In doing so we pave the way for future research that will help to break down the blockchain hype

Influence of the recycling process parameters on CFRTP waste properties

Nowadays, the combination of continuous fibers and thermoplastic polymers as the matrix to continuous fiber-reinforced thermoplastics (CFRTP) is receiving increasing attention due to their potential advantages such as excellent weight-specific mechanical properties, short cycle times, storability, repeated meltability, good formability and the use of alternative joining processes enabling automated large volume manufacturing processes which allow various applications in different industries including transportation, construction among others. As the production rate of these materials increases, the amount of waste for disposal increases, for which recycling strategies need to be established to ensure the sustainability of CFRTP. Hence, these recycling strategies must be developed and evaluated economically and ecologically to close the loop and achieve a circular economy to process recycled fiber-reinforced pellets from CFRTP waste to valuable products e.g., by injection molding. This study presents a mechanical recycling approach from CFRTP waste to injection molded test specimens and evaluates the impact of the individual recycling steps along the recycling chain on the fiber length as the fiber length is detrimental to the resulting mechanical properties. First, the CFRTP waste processability is investigated and conditions for size reduction by cutting and shredding into feedstock for extrusion are defined. Second, fiber-reinforced pellets are produced by twin-screw extrusion. The fiber volume content and the process parameters screw speed and temperature during compounding are varied and the influence of these parameters on the fiber length is determined. Third, the extruded pellets are further processed by injection molding. Here, the influence of screw speed, back pressure, and processing temperature as well as the initial fiber length in the extruded granules on the resulting properties is investigated. Quantitative correlations between material properties and processing parameters are presented and suggestions for gentle processing during recycling are given

Predicting Intentions to Read Suicide Awareness Stories: The Role of Depression and Characteristics of the Suicidal Role Model

Background: Research on factors that influence the intention to read suicide awareness material is lacking. Aims: To identify how social and state similarities between the featured protagonist of a suicide awareness story and the audience impact on the intent to read similar stories. Method: Laboratory experiment with n = 104 students. Participants were randomly assigned to study groups. In the first group, the role model provided his personal story of crisis and was a student. In the second group, the content was identical but the model was socially dissimilar. The third group read about a topic unrelated to suicide. Depression, identification, and exposure intent were measured after the experiment. Conditional process analysis was carried out. Results: In the group featuring a once-suicidal role model with high social similarity, depression in the audience increased the intention to read similar material in the future via identification with the role model; 82% of individuals wanted to read similar material in the future, but only 50% wanted to do so in the group featuring a dissimilar person. Conclusion: Exposure intention increases via identification when role model and audience characteristics align regarding social traits and the experience of depression. These factors are relevant when developing campaigns targeting individuals with stories of recovery