16,073 research outputs found

    Credit Cycle and Adverse Selection Effects in Consumer Credit Markets – Evidence from the HELOC Market

    Get PDF
    We empirically study how the underlying riskiness of the pool of home equity line of credit originations is affected over the credit cycle. Drawing from the largest existing database of U.S. home equity lines of credit, we use county-level aggregates of these loans to estimate panel regressions on the characteristics of the borrowers and their loans, and competing risk hazard regressions on the outcomes of the loans. We show that when the expected unemployment risk of households increases, riskier households tend to borrow more. As a consequence, the pool of households that borrow on home equity lines of credit worsens along both observable and unobservable dimensions. This is an interesting example of a type of dynamic adverse selection that can worsen the risk characteristics of new lending, and suggests another avenue by which the precautionary demand for liquidity may affect borrowing.Home equity loan;adverse selection;liquidity;consumption;housing finance

    A method to estimate the significance of coincident gravitational-wave observations from compact binary coalescence

    Full text link
    Coalescing compact binary systems consisting of neutron stars and/or black holes should be detectable with upcoming advanced gravitational-wave detectors such as LIGO, Virgo, GEO and {KAGRA}. Gravitational-wave experiments to date have been riddled with non-Gaussian, non-stationary noise that makes it challenging to ascertain the significance of an event. A popular method to estimate significance is to time shift the events collected between detectors in order to establish a false coincidence rate. Here we propose a method for estimating the false alarm probability of events using variables commonly available to search candidates that does not rely on explicitly time shifting the events while still capturing the non-Gaussianity of the data. We present a method for establishing a statistical detection of events in the case where several silver-plated (3--5σ\sigma) events exist but not necessarily any gold-plated (>5σ>5\sigma) events. We use LIGO data and a simulated, realistic, blind signal population to test our method

    MONTAGE: AGB nucleosynthesis with full s-process calculations

    Full text link
    We present MONTAGE, a post-processing nucleosynthesis code that combines a traditional network for isotopes lighter than calcium with a rapid algorithm for calculating the s-process nucleosynthesis of the heavier isotopes. The separation of those parts of the network where only neutron-capture and beta-decay reactions are significant provides a substantial advantage in computational efficiency. We present the yields for a complete set of s-process isotopes for a 3 Mo, Z = 0.02 stellar model, as a demonstration of the utility of the approach. Future work will include a large grid of models suitable for use in calculations of Galactic chemical evolution.Comment: 9 pages, 4 figures. Accepted by PAS

    Dry matter yields and quality of organic lupin/cereal mixtures for wholecrop forage

    Get PDF
    In view of climate change predictions and the general desirability of increasing the amount of home grown protein, a case exists for the investigation of lupins and lupin/cereal bicrop combinations as wholecrop forage on organic farms. A replicated randomised block trial is described which took place at the Royal Agricultural College, Cirencester, in 2005. This involved spring sown blue, white and yellow lupins, millet, wheat and triticale and lupin/cereal bi-crops. Data for dry matter yields for wholecrop silage, crude protein, MAD fi bre content and estimated ME, are presented for a single harvest. It is concluded that white lupins and white lupin bi-crops with spring wheat or triticale offer the best prospects for a viable wholecrop forage crop in an organic situation

    Tamari Lattices and the symmetric Thompson monoid

    Full text link
    We investigate the connection between Tamari lattices and the Thompson group F, summarized in the fact that F is a group of fractions for a certain monoid F+sym whose Cayley graph includes all Tamari lattices. Under this correspondence, the Tamari lattice operations are the counterparts of the least common multiple and greatest common divisor operations in F+sym. As an application, we show that, for every n, there exists a length l chain in the nth Tamari lattice whose endpoints are at distance at most 12l/n.Comment: 35page

    Fuselage shell and cavity response measurements on a DC-9 test section

    Get PDF
    A series of fuselage shell and cavity response measurements conducted on a DC-9 aircraft test section are described. The objectives of these measurements were to define the shell and cavity model characteristics of the fuselage, understand the structural-acoustic coupling characteristics of the fuselage, and measure the response of the fuselage to different types of acoustic and vibration excitation. The fuselage was excited with several combinations of acoustic and mechanical sources using interior and exterior loudspeakers and shakers, and the response to these inputs was measured with arrays of microphones and accelerometers. The data were analyzed to generate spatial plots of the shell acceleration and cabin acoustic pressure field, and corresponding acceleration and pressure wavenumber maps. Analysis and interpretation of the spatial plots and wavenumber maps provided the required information on modal characteristics, structural-acoustic coupling, and fuselage response

    Identifying galaxy candidates in WSRT HI imaging of ultra-compact high velocity clouds

    Get PDF
    Ultra-compact high velocity clouds (UCHVCs) were identified in the ALFALFA HI survey as potential gas-bearing dark matter halos. Here we present higher resolution neutral hydrogen (HI) observations of twelve UCHVCS with the Westerbork Synthesis Radio Telescope (WSRT). The UCHVCs were selected based on a combination of size, isolation, large recessional velocity and high column density as the best candidate dark matter halos. The WSRT data were tapered to image the UCHVCs at 210" (comparable to Arecibo) and 105" angular resolution. In a comparison of the single-dish to interferometer data, we find that the line flux recovered in the WSRT observations is comparable to that from the single-dish ALFALFA data. In addition, any structure seen in the ALFALFA data is reproduced in the WSRT maps at the same angular resolution. At 210'" resolution all the sources are generally compact with a smooth HI morphology, as expected from their identification as UCHVCs. At the higher angular resolution, a majority of the sources break into small clumps contained in a diffuse envelope. These UCHVCs also have no ordered velocity motion and are most likely Galactic halo clouds. We identify two UCHVCs, AGC 198606 and AGC 249525, as excellent galaxy candidates based on maintaining a smooth HI morphology at higher angular resolution and showing ordered velocity motion consistent with rotation. A third source, AGC 249565, lies between these two populations in properties and is a possible galaxy candidate. If interpreted as gas-bearing dark matter halos, the three candidate galaxies have rotation velocities of 8-15 km/s, HI masses of 0.6-50 x 10^5 Msun, HI radii of 0.3-2 kpc, and dynamical masses of 2-20 x 10^7 Msun for a range of plausible distances. These are the UCHVCs with the highest column density values in the ALFALFA HI data and we suggest this is the best way to identify further candidates.Comment: Accepted for publication in A&A. 26 pages, 19 figures, 5 table

    MUSE Illuminates Channels for Lyman Continuum Escape in the Halo of SBS 0335-52E

    Full text link
    We report on the discovery of ionised gas filaments in the circum-galactic halo of the extremely metal-poor compact starburst SBS 0335-052E in a 1.5h integration with the MUSE integral-field spectrograph. We detect these features in Hα{\alpha} and [OIII] emission down to surface-brightness levels of 5×10195 \times 10^{-19}erg s1^{-1}cm2^{-2}arcsec2^{-2}. The filaments have projected diameters of 2.1 kpc and extend more than 9 kpc to the north and north-west from the main stellar body. We also detect extended nebular HeII λ\lambda4686 emission that brightens towards the north-west at the rim of a star-burst driven super-shell, suggestive of a locally enhanced UV radiation field due to shocks. We also present a velocity field of the ionised gas. The filaments appear to connect seamlessly in velocity space to the kinematical disturbances caused by the shell. Similar to high-zz star-forming galaxies, the ionised gas in this galaxy is dispersion dominated. We argue that the filaments were created via feedback from the starburst and that these ionised structures in the halo may act as escape channels for Lyman continuum radiation in this gas-rich system.Comment: Revised version after peer review. Accepted for publication in A&A letter
    corecore