2,917 research outputs found
Are some fund managers better than others? Manager characteristics and fund performance
CITATION: Friis, L. B. & Smit, E. v d M. 2004. Are some fund managers better than others? Manager characteristics and fund performance. South African Journal of Business Management, 35(3):a660, doi:10.4102/sajbm.v35i3.660.The original publication is available at https://sajbm.orgThe research objective has been to find out whether fund manager characteristics help explain fund performance and propensity to risk taking. Eight independent variables; manager age, tenure of the manager with the fund, years of education, whether the manager holds a MBA or CA/CFA qualification, management team size, fund age and fund objective are regressed on measures of fund performance and riskiness.
The findings of the study are highly significant and show that fund performance and riskiness are impacted upon by managers’ qualifications. One can expect better risk-adjusted performance from a fund manager who holds a CA/CFA qualification. Results show that these managers outperform managers without these qualifications, while taking on less risk than managers with MBA qualifications.https://sajbm.org/index.php/sajbm/article/view/660Publisher's versio
Screening of the topological charge in a correlated instanton vacuum
Screening of the topological charge due to he fermion-induced interactions is
an important phenomenon, closely related with the resolution of the strong CP
and U(1) problems. We study the mechanism of such screening in a 'correlated
instanton vacuum', as opposed to the 'random' one. Both scalar and pseudoscalar
gluonic correlators are analyzed by means of an observable that minimizes
finite size effects. Screening of the topological charge is established. This
allows us to calculate the mass without having to invert the Dirac
operator. We suggest that this method might be used in lattice QCD calculations
as well. Our results for the screening of the topological charge are in
agreement with the chiral Ward identities, and the scalar gluonic correlator
satisfies a low energy theorem first derived by Novikov et al.
\cite{Novikov-etal}. We also propose to evaluate the topological susceptibility
in the Witten-Veneziano formula not in an infinite box in an world
fermions but in an infinitesimal box in a world fermions.Comment: 22 pages + 5 postscript figures, SUNY-NTG/94-25. Corrected LATEX
erro
Gas exchange during storage and incubation of Avian eggs: Effects on embryogenesis, hatchability, chick quality and post-hatch growth
Embryonic development is a dynamic process that requires a fine balance between several factors in order to achieve an optimum hatchability and chick quality. These factors include the background of the embryo, such as genetic line of the breeders, the age of the breeder, egg weight, and factors related to the environment in which the egg is stored and incubated, such as temperature, humidity, gas levels and altitude. Gas exchanges are of fundamental importance for embryonic development during incubation and may affect the livability of the embryo. This paper reviews the roles of the gaseous environment (i.e. O 2 and CO2) around hatching eggs during storage and during incubation and the effect it might have on the survival of the developing embryos and the chicks that hatch. The state of the art on the different attempts to establish the optimum requirements of different gases that promote the optimal developmental trajectories at different periods during incubation is presented. The roles and consequences of different levels of O2 and CO2 during storage and incubation on hatchability, incubation duration, hatching process, embryo growth, embryo mortality, organ development and morphology, metabolism, blood acid-base balance, chick quality and chick post-hatch growth are reviewed. © 2007 World's Poultry Science Association
Investigation of the Domain Wall Fermion Approach to Chiral Gauge Theories on the Lattice
We investigate a recent proposal to construct chiral gauge theories on the
lattice using domain wall fermions. We restrict ourselves to the finite volume
case, in which two domain walls are present, with modes of opposite chirality
on each of them. We couple the chiral fermions on only one of the domain walls
to a gauge field. In order to preserve gauge invariance, we have to add a
scalar field, which gives rise to additional light mirror fermion and scalar
modes. We argue that in an anomaly free model these extra modes would decouple
if our model possesses a so-called strong coupling symmetric phase. However,
our numerical results indicate that such a phase most probably does not exist.
---- Note: 9 Postscript figures are appended as uuencoded compressed tar file.Comment: 27p. Latex; UCSD/PTH 93-28, Wash. U. HEP/93-6
Isotopic Production Cross Sections in Proton-Nucleus Collisions at 200 MeV
Intermediate mass fragments (IMF) from the interaction of Al,
Co and Au with 200 MeV protons were measured in an angular range
from 20 degree to 120 degree in the laboratory system. The fragments, ranging
from isotopes of helium up to isotopes of carbon, were isotopically resolved.
Double differential cross sections, energy differential cross sections and
total cross sections were extracted.Comment: accepted by Phys. Rev.
Phase Coexistence of a Stockmayer Fluid in an Applied Field
We examine two aspects of Stockmayer fluids which consists of point dipoles
that additionally interact via an attractive Lennard-Jones potential. We
perform Monte Carlo simulations to examine the effect of an applied field on
the liquid-gas phase coexistence and show that a magnetic fluid phase does
exist in the absence of an applied field. As part of the search for the
magnetic fluid phase, we perform Gibbs ensemble simulations to determine phase
coexistence curves at large dipole moments, . The critical temperature is
found to depend linearly on for intermediate values of beyond the
initial nonlinear behavior near and less than the where no
liquid-gas phase coexistence has been found. For phase coexistence in an
applied field, the critical temperatures as a function of the applied field for
two different are mapped onto a single curve. The critical densities
hardly change as a function of applied field. We also verify that in an applied
field the liquid droplets within the two phase coexistence region become
elongated in the direction of the field.Comment: 23 pages, ReVTeX, 7 figure
An empirical framework of control methods of victims of human trafficking for sexual exploitation
Although human trafficking for sexual exploitation is a frequently discussed area in current research, especially on the way that human traffickers control their victims, a recurrent problem is the lack of empirical basis. The present study examines control methods (or conditions) used against 137 victims of human trafficking for sexual exploitation. A multidimensional scaling analysis (smallest space analysis (SSA-I)) of 23 control methods (and conditions) derived from a content analysis of police files from the Netherlands revealed three distinct forms of control. These could be interpreted in terms of Canter’s Victim Role model that has been the basis for differentiating offending styles in other violent interpersonal offences. Further analysis showed a relationship between these control styles and different types of prostitution. The three Victim as Object, Victim as Vehicle and Victim as Person modes are consistent with different control methods identified in previous research
Spontaneous symmetry breaking in strong-coupling lattice QCD at high density
We determine the patterns of spontaneous symmetry breaking in strong-coupling
lattice QCD in a fixed background baryon density. We employ a
next-nearest-neighbor fermion formulation that possesses the SU(N_f)xSU(N_f)
chiral symmetry of the continuum theory. We find that the global symmetry of
the ground state varies with N_f and with the background baryon density. In all
cases the condensate breaks the discrete rotational symmetry of the lattice as
well as part of the chiral symmetry group.Comment: 10 pages, RevTeX 4; added discussion of accidental degeneracy of
vacuum after Eq. (35
Studies of the Giant Dipole Resonance in Al, Ca, Fe, Ni and Pb with high energy-resolution inelastic proton scattering under 0
A survey of the fine structure of the Isovector Giant Dipole Resonance
(IVGDR) was performed, using the recently commissioned zero-degree facility of
the K600 magnetic spectrometer at iThemba LABS. Inelastic proton scattering at
an incident energy of 200 MeV was measured on Al, Ca, Fe,
Ni and Pb. A high energy resolution (
40 keV FWHM) could be achieved after utilising faint-beam and
dispersion-matching techniques. Considerable fine structure is observed in the
energy region of the IVGDR and characteristic energy scales are extracted from
the experimental data by means of a wavelet analysis. The comparison with
Quasiparticle-Phonon Model (QPM) calculations provides insight into the
relevance of different giant resonance decay mechanisms. Photoabsorption cross
sections derived from the data assuming dominance of relativistic Coulomb
excitation are in fair agreement with previous work using real photons.Comment: 15 pages, 15 figure
Magnetization of densely packed interacting magnetic nanoparticles with cubic and uniaxial anisotropies: A Monte Carlo study
International audienceThe magnetization curves of densely packed single domain magnetic nanoparticles (MNP) are investigated by Monte Carlo simulations in the framework of an effective one spin model. The particles whose size polydispersity is taken into account are arranged in spherical clusters and both dipole dipole interactions (DDI) and magnetic anisotropy energy (MAE) are included in the total energy. Having in mind the special case of spinel ferrites of intrinsic cubic symmetry, combined cubic and uniaxial magnetocrystalline anisotropies are considered with different configurations for the orientations of the cubic and uniaxial axes. It is found that the DDI, together with a marked reduction of the linear susceptibility are responsible for a damping of the peculiarities due to the MAE cubic component on the magnetization. As an application, we show that the simulated magnetization curves compare well to experimental results for --FeO MNP for small to moderate values of the field
- …