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Florian Huber

Publications and source records attributed to Florian Huber.

81 records · Page 5Linked to original sources

The transmission of uncertainty shocks on income inequality: State-level evidence from the United States

In this paper, we explore the relationship between state-level household income inequality and macroeconomic uncertainty in the United States. Using a novel large-scale macroeconometric model, we shed light on regional disparities of inequality responses to a national uncertainty shock. The results suggest that income inequality decreases in most states, with a pronounced degree of heterogeneity in terms of shapes and magnitudes of the dynamic responses. By contrast, some few states, mostly located in the West and South census region, display increasing levels of income inequality over time. We find that this directional pattern in responses is mainly driven by the income composition and labor market fundamentals. In addition, forecast error variance decompositions allow for a quantitative assessment of the importance of uncertainty shocks in explaining income inequality. The findings highlight that volatility shocks account for a considerable fraction of forecast error variance for most states considered. Finally, a regression-based analysis sheds light on the driving forces behind differences in state-specific inequality responses.

econ.EM↗

The dynamic impact of monetary policy on regional housing prices in the US: Evidence based on factor-augmented vector autoregressions

In this study interest centers on regional differences in the response of housing prices to monetary policy shocks in the US. We address this issue by analyzing monthly home price data for metropolitan regions using a factor-augmented vector autoregression (FAVAR) model. Bayesian model estimation is based on Gibbs sampling with Normal-Gamma shrinkage priors for the autoregressive coefficients and factor loadings, while monetary policy shocks are identified using high-frequency surprises around policy announcements as external instruments. The empirical results indicate that monetary policy actions typically have sizeable and significant positive effects on regional housing prices, revealing differences in magnitude and duration. The largest effects are observed in regions located in states on both the East and West Coasts, notably California, Arizona and Florida.

econ.EM↗

Predicting crypto-currencies using sparse non-Gaussian state space models

In this paper we forecast daily returns of crypto-currencies using a wide variety of different econometric models. To capture salient features commonly observed in financial time series like rapid changes in the conditional variance, non-normality of the measurement errors and sharply increasing trends, we develop a time-varying parameter VAR with t-distributed measurement errors and stochastic volatility. To control for overparameterization, we rely on the Bayesian literature on shrinkage priors that enables us to shrink coefficients associated with irrelevant predictors and/or perform model specification in a flexible manner. Using around one year of daily data we perform a real-time forecasting exercise and investigate whether any of the proposed models is able to outperform the naive random walk benchmark. To assess the economic relevance of the forecasting gains produced by the proposed models we moreover run a simple trading exercise.

econ.EM↗

Pushing STEM-education through a social-media-based contest format - experiences and lessons-learned from the H2020-project SciChallenge

Science education is a crucial issue with long-term impacts for Europe as the low enrolment rates in the STEM-fields, including (natural) science, technology, engineering and mathematics, will lead to a workforce problem in research and development. In order to address this challenge, the EU-funded research project SciChallenge (project.scichallenge.eu) aims to find a new way for getting young people more interested in STEM. For this purpose, the project developed and implemented a social-media-based STEM-contest for young people, which aims at increasing the attractiveness of science education and careers among young people. In the first two parts, the paper reflects on the problem, introduces the project and highlights the main steps of the preparation of the contest. The third section of the paper presents the idea, design and implementation of the digital contest platform (www.scichallenge.eu), which serves as the core of the challenge. The fourth part of the paper will provide a status update on the contest pilot. It will provide a summary of the experiences that the consortium made with this novel approach as well as the main obstacles that the consortium was facing. The paper will conclude with a preliminary reflection on the question if such an approach can help to increase the interest of young people in STEM-education and careers.

cs.CY↗

SciChallenge: Using Student-Generated Content and Contests to Enhance the Interest for Science Education and Careers

Science education will play a vital role in shaping the present and future of modern societies. Thus, Europe needs all its talents to increase creativity and competitiveness. Young boys and girls especially have to be engaged to pursue careers in Science, Technology, Engineering and Mathematics (STEM). However, statistics still show that enrolment rates in STEM-based degree programs are decreasing. This will lead to a workforce problem in the industrial sector as well as in research and development, especially in many of the new member countries. This paper highlights a recently funded EU-research project SciChallenge (www.scichallenge.eu), which focuses on the development of novel concepts to get young people excited about science education. It uses a contest-based approach towards self-produced digital education materials from young people for young people. In cooperation with partner schools, teachers, and other youth-oriented institutions, the contest participants (individuals or groups) between the ages of 10 and 20 years generate creative digital materials (videos, slides, or infographics). The participants upload their content in social media channels and the submissions are aggregated on the SciChallenge Web Platform. The winners receive prizes funded by science-oriented industry and other stakeholders. Intelligent cross-sectoral positioning of various awareness modules on the SciChallenge Open Information Hub is expected to increase awareness on science careers. Through a strong involvement of related organizations and industries, we expect to open new opportunities for young people in regards to internships or taster days in STEM disciplines. Additionally, aggregated information on science events (such as, slams, nights, festivals) is shared. With this multi-level approach, SciChallenge may boost the attractiveness of science education and careers among young people.

cs.CY↗

Site-resolved imaging of a fermionic Mott insulator

The complexity of quantum many-body systems originates from the interplay of strong interactions, quantum statistics, and the large number of quantum-mechanical degrees of freedom. Probing these systems on a microscopic level with single-site resolution offers important insights. Here we report site-resolved imaging of two-component fermionic Mott insulators, metals, and band insulators using ultracold atoms in a square lattice. For strong repulsive interactions we observe two-dimensional Mott insulators containing over 400 atoms. For intermediate interactions, we observe a coexistence of phases. From comparison to theory we find trap-averaged entropies per particle of $1.0\,k_{\mathrm{B}}$. In the band-insulator we find local entropies as low as $0.5\,k_{\mathrm{B}}$. Access to local observables will aid the understanding of fermionic many-body systems in regimes inaccessible by modern theoretical methods.

cond-mat.quant-gas↗

Site-resolved Imaging of Fermionic Lithium-6 in an Optical Lattice

We demonstrate site-resolved imaging of individual fermionic lithium-6 atoms in a 2D optical lattice. To preserve the density distribution during fluorescence imaging, we simultaneously cool the atoms with 3D Raman sideband cooling. This laser cooling technique, demonstrated here for the first time for lithium-6 atoms, also provides a pathway to rapid low-entropy filling of an optical lattice. We are able to determine the occupation of individual lattice sites with a fidelity >95%, enabling direct, local measurement of particle correlations in Fermi lattice systems. This ability will be instrumental for creating and investigating low-temperature phases of the Fermi-Hubbard model, including antiferromagnets and d-wave superfluidity.

cond-mat.quant-gas↗

Interfacing light and single atoms with a lens

We characterize the interaction between a single atom or similar microscopic system and a light field via the scattering ratio. For that, we first derive the electrical field in a strongly focused Gaussian light beam, and then consider the atomic response. Following the simple scattering model, the fraction of scattered optical power for a weak coherent probe field leads to unphysical scattering ratios above 1 in the strong focusing regime. A refined model considering interference between exciting and scattered field into finite-sized detectors or optical fibers is presented, and compared to experimental extinction measurements for various focusing strengths.

quant-ph↗

Strong interaction between light and a single trapped atom without a cavity

Coupling of light to an atom at single quanta level with high probability is a building block for many quantum information processing protocols. It is commonly believed that efficient coupling is only achievable with the assistance of a cavity. Here, we report on an observation of substantial coupling between a light beam and a single $^{87}$Rb atom in a direct extinction measurement by focusing light to a small spot with a single lens. Our result opens a new perspective on processing quantum information carried by light using atoms, and is important to many ongoing experiments that require strong coupling of single photons to an atom in free space.

quant-ph↗