6,078 research outputs found
Solving discrete time heterogeneous agent models with aggregate risk and many idiosyncratic states by perturbation
This paper describes a method for solving heterogeneous agent models with aggregate risk and many idiosyncratic states formulated in discrete time. It extends the method proposed by Reiter (2009) and complements recent work by Ahn, Kaplan, Moll, Winberry, and Wolf (2017) on how to solve such models in continuous time. We suggest first solving for the stationary equilibrium of the model without aggregate risk. We then write the functionals that describe the dynamic equilibrium as sparse expansions around their stationary equilibrium counterparts. Finally, we use the perturbation method of Schmitt‐Grohé and Uribe (2004) to approximate the aggregate dynamics of the model
Discounts and Consumer Search Behavior: The Role of Framing
We implement a simple two-shop search model in the laboratory with the aim to investigate if consumers behave differently in equivalent situations, where prices are displayed either as net prices or as gross prices with discounts. We compare treatments, where we either depict the known price of the first shop or the initially uncertain price of the second shop as a gross price with a discount, with treatments without discounts. We ind that subjects search less in both treatments with discounts. Hence, we conclude that retailers can use this framing effect in order to reduce the competitiveness in their market, since decreased search intensities dampen competitive pressure
Affine and toric hyperplane arrangements
We extend the Billera-Ehrenborg-Readdy map between the intersection lattice
and face lattice of a central hyperplane arrangement to affine and toric
hyperplane arrangements. For arrangements on the torus, we also generalize
Zaslavsky's fundamental results on the number of regions.Comment: 32 pages, 4 figure
Level Eulerian Posets
The notion of level posets is introduced. This class of infinite posets has
the property that between every two adjacent ranks the same bipartite graph
occurs. When the adjacency matrix is indecomposable, we determine the length of
the longest interval one needs to check to verify Eulerianness. Furthermore, we
show that every level Eulerian poset associated to an indecomposable matrix has
even order. A condition for verifying shellability is introduced and is
automated using the algebra of walks. Applying the Skolem--Mahler--Lech
theorem, the -series of a level poset is shown to be a rational
generating function in the non-commutative variables and .
In the case the poset is also Eulerian, the analogous result holds for the
-series. Using coalgebraic techniques a method is developed to
recognize the -series matrix of a level Eulerian poset
Coexpression, copurification, crystallization and preliminary X-ray analysis of a complex of ARL2-GTP and PDE delta
The small GTPase ARL2 (from Mus musculus) and an effector protein, the δ subunit of human cGMP phosphodiesterase (hPDE δ), were coexpressed and copurified from Escherichia coli as a stable complex. Coexpression significantly increased the otherwise low yield of PDE δ production in E. coli. The complex, which contains ARL2 in the activated GTP-bound form, was crystallized in two forms. The first belongs to the monoclinic space group P21, with unit-cell parameters a = 48.1, b = 45.7, c = 74.7 Å, β = 94.0° and one complex (39 kDa) in the asymmetric unit. Cryocooled crystals diffract to 2.3 Å using synchrotron radiation. The micro-focused X-ray beam at beamline ID13 (ESRF) allowed the use of very small crystals, which helped to overcome twinning and enabled the identification of a molecular-replacement solution. The second form recrystallized from the first one after several months. These crystals belong to the orthorhombic space group P212121, with unit-cell parameters a = 44.5, b = 65.4, c = 104.4 Å and one complex in the asymmetric unit. They diffracted to 1.8 Å using synchrotron radiation
Structural and magnetic properties of Mn3-xCdxTeO6 (x = 0, 1, 1.5 and 2)
Mn3TeO6 exhibits a corundum-related A3TeO6 structure and a complex magnetic
structure involving two magnetic orbits for the Mn atoms [*]. Mn3-xCdxTeO6
(x=0, 1, 1.5 and 2) ceramics were synthesized by solid state reaction and
investigated using X-ray powder diffraction, electron microscopy, calorimetric
and magnetic measurements. Cd2+ replaces Mn2+ cations without greatly affecting
the structure of the compound. The Mn and Cd cations were found to be randomly
distributed over the A-site. Magnetization measurements indicated that the
samples order antiferromagnetically at low temperature with a transition
temperature that decreases with increasing Cd doping. The nuclear and magnetic
structure of one specially prepared 114Cd containing sample:
Mn1.5(114Cd)1.5TeO6, was studied using neutron powder diffraction over the
temperature range 2 to 295 K. Mn1.5(114Cd)1.5TeO6 was found to order in an
incommensurate helical magnetic structure, very similar to that of Mn3TeO6 [*].
However, with a lower transition temperature and the extension of the ordered
structure confined to order 240(10) {\AA}. [*] S. A. Ivanov et al. Mater. Res.
Bull. 46 (2011) 1870.Comment: 20 pages, 8 figure
- …