Confidence Cycles

We provide a model that rationalizes variations in confidence of rational agents, both in the time-series and the cross-section. Combining horizon-dependent risk aversion (“anxiety”) and selective memory, we show that over- and underconfidence can arise in the Bayesian equilibrium of an intra-personal game. In the time-series, overconfidence is more prevalent when actual risk levels are high, while underconfidence occurs when risks are low. In the cross-section, more anxious agents are more prone to biased confidence and their beliefs fluctuate more, leading them to buy in booms and sell in crashes. Lastly, fluctuations in confidence can amplify boom-bust cycles

CR embeddings of CR manifolds

We improve results of Baouendi, Rothschild and Treves and of Hill and Nacinovich by finding a much weaker sufficient condition for a CR manifold of type (n, k) to admit a local CR embedding into a CR manifold of type (n+ ℓ, k- ℓ). While their results require the existence of a finite dimensional solvable transverse Lie algebra of vector fields, we require only a finite dimensional extension

Horizon-Dependent Risk Aversion and the Timing and Pricing of Uncertainty

We address two fundamental critiques of established asset pricing models: that they (1) require a controversial degree of preference for early resolution of uncertainty; and (2) do not match the term structures of risk premia observed in the data. Inspired by experimental evidence, we construct preferences in which risk aversion decreases with the temporal horizon. The resulting model implies term structures of risk premia consistent with the evidence, including timevariations and reversals in the slope, without imposing a particular preference for early or late resolutions of uncertainty or compromising on the ability to match standard moments in the returns distributions

Mössbauer Studies of Nickel-Iron Hydrotalcites

Hydrotalcite-like Fe-Ni-hydroxides [Ni2/3IIFe1/3III(OH)2](CO3)1/6(H2O)y , [Ni3/4IIFe1/4III(OH)2]-(CO3)1/8(H2O)y and [Ni3/4II/IIIFe1/4III(OH)2](CO3)0.14(H20)y as well as the ternary oxide NaNi2/3Fe1/3O2 have been studied by 57Fe-Mössbauer spectroscopy. All samples contain Fe3+ in a high spin state. The quadrupole interaction is smaller if a magnetic splitting is present, which may indicate a non-parallel arrangement of the principal axis of the EFG and the hyperfine field. The temperature dependence of the spectra has been understood in terms of collective cluster excitations. In this model the magnetic energy of a single domain depends on the direction of the total magnetic moment and on magnetic interaction with the neighbourhood. The spectral lineshape could be fitted assum­ing uniaxial relaxation

trans-Ethyl­enedi-p-phenyl­ene diacetate

The centrosymmetric title compound, C18H26O4, was prepared in high yield from 4-acetoxy­styrene via Ru-catalysed homo-olefin metathesis. Exclusive formation of the E-configurated isomer was observed. In the crystal, a strong C—H⋯π inter­molecular inter­action links the mol­ecules together

Field theoretic approach to the counting problem of Hamiltonian cycles of graphs

A Hamiltonian cycle of a graph is a closed path that visits each site once and only once. I study a field theoretic representation for the number of Hamiltonian cycles for arbitrary graphs. By integrating out quadratic fluctuations around the saddle point, one obtains an estimate for the number which reflects characteristics of graphs well. The accuracy of the estimate is verified by applying it to 2d square lattices with various boundary conditions. This is the first example of extracting meaningful information from the quadratic approximation to the field theory representation.Comment: 5 pages, 3 figures, uses epsf.sty. Estimates for the site entropy and the gamma exponent indicated explicitl