270,919 research outputs found
A HAZARD ANALYSIS OF CONSUMERS’ SWITCHING BEHAVIOUR IN GERMAN FOOD RETAILING FOR DAIRY PRODUCTS
German food retailing is characterized by fierce competition among retail chains for consumer shopping. This paper considers the switching behaviour using data of white dairy product purchases. The empirical investigation uses a survival analysis approach, in particular hazard analysis. The results extend the knowledge of shopping behaviour by providing a new set of explaining variables and the importance of the first store, defined as store with the major share of household budget, becomes apparent. On average, households buy dairy products 42 times per year. Thereof 58 % are retail chain switches and in 41 % of all cases the households remain at the previously visited retail chain. Generally a low customer loyalty is visible in this investigation. It is shown that switching behaviour is widely influenced - amongst others - by percentage of private label products, percentage of special offers and price consciousness.switching behaviour, store choice, store loyalty, hazard analysis, food retailing, Geschäftsstättenwahl, Geschäftsstättenwechsel, Einkaufsverhalten, Hazard Analyse, Lebensmitteleinzelhandel, Agribusiness, Agricultural and Food Policy, Agricultural Finance, Community/Rural/Urban Development, Food Consumption/Nutrition/Food Safety, Industrial Organization,
Bulk antisymmetric tensor fields in a Randall-Sundrum model
We consider bulk antisymmetric tensor fields of various ranks in a
Randall-Sundrum scenario. We show that, rank-2 onwards, the zero-modes of the
projections of these fields on the (3+1) dimensional visible brane become
increasingly weaker as the rank of the tensor increases. All such tensor fields
of rank 4 or more are absent from the dynamics in four dimensions. This leaves
only the zero-mode graviton to have coupling with matter, thus
explaining why the large-scale behaviour of the universe is governed by gravity
only. We have also computed the masses of the heavier modes upto rank-3, and
shown that they are relatively less likely to have detectable accelerator
signals.Comment: 8 Pages, Late
Vote expectations and pre-electoral tariff cuts in Flemish municipalities
Using data covering 3 election moments (1988-2000) for 294 Flemish municipalities we examine whether the decision to cut tariffs before elections depends on the government’s expectations of staying into office. Election moments are central to both the political budget cycle literature and the strategic debt models. The combination of both theories could suggest that, at least in theory, both winning and loosing governments seem to benefit from preelectoral tariff reductions and as such we expect to find a great many municipalities to engage into tariff cuts. The dataset however shows this is clearly not the case. We argue that the differences in the fiscal policy reaction of governments facing elections might have to do with their expectations of staying into office. In our analysis we make the decision to change tariffs dependent on the expected vote percentage of the government party (parties). As we do not possess reliable ex ante data on the perceived re-election probability, we estimate a vote-function to predict the percentage of votes. Our analysis shows that tariff reductions in election years are more prone when governments expect not to reach majority again in next elections
Bistability and oscillatory motion of natural nano-membranes appearing within monolayer graphene on silicon dioxide
The recently found material graphene is a truly two-dimensional crystal and
exhibits, in addition, an extreme mechanical strength. This in combination with
the high electron mobility favours graphene for electromechanical
investigations down to the quantum limit. Here, we show that a monolayer of
graphene on SiO2 provides natural, ultra-small membranes of diameters down to 3
nm, which are caused by the intrinsic rippling of the material. Some of these
nano-membranes can be switched hysteretically between two vertical positions
using the electric field of the tip of a scanning tunnelling microscope (STM).
They can also be forced to oscillatory motion by a low frequency ac-field.
Using the mechanical constants determined previously, we estimate a high
resonance frequency up to 0.4 THz. This might be favorable for
quantum-electromechanics and is prospective for single atom mass spectrometers.Comment: 9 pages, 4 figure
Young and middle age pulsar light-curve morphology: Comparison of Fermi observations with gamma-ray and radio emission geometries
Thanks to the huge amount of gamma-ray pulsar photons collected by the Fermi
Large Area Telescope since June 2008, it is now possible to constrain gamma-ray
geometrical models by comparing simulated and observed light-curve
morphological characteristics. We assumed vacuum-retarded dipole pulsar
magnetic field and tested simulated and observed morphological light-curve
characteristics in the framework of two pole emission geometries, Polar Cap
(PC), radio, and Slot Gap (SG), and Outer Gap (OG)/One Pole Caustic (OPC)
emission geometries. We compared simulated and observed/estimated light-curve
morphological parameters as a function of observable and non-observable pulsar
parameters. The PC model gives the poorest description of the LAT pulsar
light-curve morphology. The OPC best explains both the observed gamma-ray peak
multiplicity and shape classes. The OPC and SG models describe the observed
gamma-ray peak-separation distribution for low- and high-peak separations,
respectively. This suggests that the OPC geometry best explains the single-peak
structure but does not manage to describe the widely separated peaks predicted
in the framework of the SG model as the emission from the two magnetic
hemispheres. The OPC radio-lag distribution shows higher agreement with
observations suggesting that assuming polar radio emission, the gamma-ray
emission regions are likely to be located in the outer magnetosphere. The
larger agreement between simulated and LAT estimations in the framework of the
OPC suggests that the OPC model best predicts the observed variety of profile
shapes. The larger agreement between observations and the OPC model jointly
with the need to explain the abundant 0.5 separated peaks with two-pole
emission geometries, calls for thin OPC gaps to explain the single-peak
geometry but highlights the need of two-pole caustic emission geometry to
explain widely separated peaks.Comment: 28 pages, 20 figures, 8 tables; accepted for publication in Astronomy
and Astrophysic
Descartes, corpuscles and reductionism : mechanism and systems in Descartes' physiology
I argue that Descartes explains physiology in terms of whole systems, and not in terms of the size, shape and motion of tiny corpuscles (corpuscular mechanics). It is a standard, entrenched view that Descartes’s proper means of explanation in the natural world is through strict reduction to corpuscular mechanics. This view is bolstered by a handful of corpuscular-mechanical explanations in Descartes’s physics, which have been taken to be representative of his treatment of all natural phenomena. However, Descartes’s explanations of the ‘principal parts’ of physiology do not follow the corpuscular–mechanical pattern. Des Chene (2001) has identified systems in Descartes’s account of physiology, but takes them ultimately to reduce down to the corpuscle level. I argue that they do not. Rather, Descartes maintains entire systems, with components selected from multiple levels of organisation, in order to construct more complete explanations than corpuscular mechanics alone would allow
Towards Viable Cosmological Models of Disformal Theories of Gravity
The late-time cosmological dynamics of disformal gravity are investigated
using dynamical systems methods. It is shown that in the general case there are
no stable attractors that screen fifth-forces locally and simultaneously
describe a dark energy dominated universe. Viable scenarios have late-time
properties that are independent of the disformal parameters and are identical
to the equivalent conformal quintessence model. Our analysis reveals that
configurations where the Jordan frame metric becomes singular are only reached
in the infinite future, thus explaining the natural pathology resistance
observed numerically by several previous works. The viability of models where
this can happen is discussed in terms of both the cosmological dynamics and
local phenomena. We identify a special parameter tuning such that there is a
new fixed point that can match the presently observed dark energy density and
equation of state. This model is unviable when the scalar couples to the
visible sector but may provide a good candidate model for theories where only
dark matter is disformally coupled.Comment: Updated to reflect the published versio
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