Superconducting zero temperature phase transition in two dimensions and in the magnetic field

We derive the Ginzburg-Landau-Wilson theory for the superconducting phase transition in two dimensions and in the magnetic field. Without disorder the theory describes a fluctuation induced first-order quantum phase transition into the Abrikosov lattice. We propose a phenomenological criterion for determining the transition field and discuss the qualitative effects of disorder. Comparison with recent experiments on MoGe films is discussed.Comment: 7 pages, 2 figure

Imperfect Information and Investor Inferences From Housing Price Dynamics

We examine characteristics of housing price dynamics that may be consistent with rational learning and not simply irrational feedback trading. We find significant patterns of temporal and spatial diffusion that are more amenable to explanations that allow for rational components. First, we execute our tests not simply on housing price changes, but on town-by-town differentials from regional average price changes. Second, we find significant relationships with own and neighboring town differentials, but not with control groups of non-neighboring towns. Third, we find that population density, a proxy for scale economies in information production, accelerates the diffusion process. Test were performed on quarterly data for large samples from Connecticut and the San Francisco area, employing method of moments estimators. Copyright American Real Estate and Urban Economics Association.

Temporal and Spatial Information Diffusion in Real Estate Price Changes and Variances

This article examines patterns of temporal and spatial diffusion of real estate price changes. In addition to means, changes in volatility are tracked in reaction to substantial new information, estimated with GARCH-M methods. The data covers towns in Connecticut and near San Francisco. There is evidence of negative feedback at short lags, contrary to previous research on housing and other assets. There is also evidence of a moving average error process which tends to reverse recent shocks. Significantly positive spatial information diffusion is found from neighboring towns in Connecticut but none in control tests on nonneighboring towns. The results also include evidence of a risk-reward tradeoff in housing price changes in the San Francisco area. Copyright American Real Estate and Urban Economics Association.