Decisions to Renovate and to Move

Housing renovation is the main alternative means of housing supply besides construction of new housing. Relatively little is known about the factors that affect decisions by households about whether to renovate and which sort of renovations to undertake. These questions are explored empirically. Separate analyses are conducted of the decision to undertake "major structural renovations" as opposed to other sorts (such as remodeling the kitchen or bathroom), and also of the decision to conduct renovations that add to the living space of the housing unit. Financial, household and geographic factors affecting this decision are analyzed econometrically.

The Inversion of the Land Gradient in the Inner City of Haifa, Israel

While suburbanization and decentralization are familiar concepts in urban economics, there is a possibility that land gradients will not simply flatten over time, but actually invert themselves. This would mean that the traditional CBD or downtown ceases to act as the pinnacle or nucleus of the land/housing pricing function within the metropolitan area. Such a possibility has been noted in the theoretical literature and has been demonstrated empirically in a few cases. Such an urban ‘‘inversion’’ is shown to have occurred in Haifa, Israel. Beginning in the 1960s, the stock of privately-owned cars grew in Israel at one of the most rapid rates ever seen in any industrial country, with relatively little growth in transportation infrastructure.

Reynolds stresses and mean fields generated by pure waves: applications to shear flows and convection in a rotating shell

A general reformulation of the Reynolds stresses created by two-dimensional waves breaking a translational or a rotational invariance is described. This reformulation emphasizes the importance of a geometrical factor: the slope of the separatrices of the wave flow. Its physical relevance is illustrated by two model systems: waves destabilizing open shear flows; and thermal Rossby waves in spherical shell convection with rotation. In the case of shear-flow waves, a new expression of the Reynolds–Orr amplification mechanism is obtained, and a good understanding of the form of the mean pressure and velocity fields created by weakly nonlinear waves is gained. In the case of thermal Rossby waves, results of a three-dimensional code using no-slip boundary conditions are presented in the nonlinear regime, and compared with those of a two-dimensional quasi-geostrophic model. A semi-quantitative agreement is obtained on the flow amplitudes, but discrepancies are observed concerning the nonlinear frequency shifts. With the quasi-geostrophic model we also revisit a geometrical formula proposed by Zhang to interpret the form of the zonal flow created by the waves, and explore the very low Ekman-number regime. A change in the nature of the wave bifurcation, from supercritical to subcritical, is found

The Institutional Structure and the Cost of Bank Loans: an International Comparison

In recent years international comparisons emphasized the importance of institutional and legal factors in capital market development and the performance of private firms. Here that approach is applied to the pricing of bank loans. Loan rates depend on contract parameters such as risk, the existence of covenants and loan size. Syndicate structure and the number of lenders also determine the cost of borrowing. Loan prices are also negatively impacted if the lending banks operate as part of larger conglomerates. Loan prices are also shown to depend on a number of institutional factors, such as the quality of protection of creditor rights and the quality of law enforcement. Curiously, we find that contracts with customers in "French tradition" countries were priced lower, as if having lower risk, than others, other things held equal. This is not in line with other segments of the literature on international capital market differences and institutional factors. It suggests that differences across legal traditions are more complicated than previously understood

Water policy in California and Israel

Water policies throughout the world often avoid market-determined allocations. In this article, we focus on case studies of Israel and California. Despite major cultural and political differences, it is found that water is heavilty controlled through similar administrative mechanisms in both areas. Moreover, in both cases, these controls have led to inefficient allocation schemes favoring agriculture at the expense of other uses. This article examines the institutional factors that have led to such controls, and argues that adopting a new regulatory framework similar to that used to regulate electricity can still meet social concerns while dramatically improving economic efficiency.Water-supply - California ; California ; Israel

On the stability of some continuous systems subjected to random excitation

Conditions determined for sure stability of continuous systems subjected to random excitatio

On the stability of a column subjected to a time-dependent axial load

Exponential bounds and stability conditions for linear elastic column subjected to time varying axial loa

Radar scattering from desert terrains, Pisgah/Lavic Region, California: Implications for Magellan

A major component of the 1988 Mojave Field Experiment involved the simultaneous acquisition of quad-polarization multifrequency airborne Synthetic Aperture Radar (SAR) imaging radar data and ground measurements thought to be relevant to the radar scattering behavior of a variety of desert surfaces. In preparation for the Magellan mission to Venus, the experiment was designed to explore the ability of SAR to distinguish types of geological surfaces, and the effects of varying incidence angles on the appearance of such surfaces. The airborne SAR system acquired images at approx. 10 m resolution, at 3 incidence angles (30, 40, 50 degs) and at 3 wavelengths (P:68 cm, L:24 cm, C:5.6 cm). The polarimetric capabilities of the instrument allow the simulation of any combination of transmit and receive polarizations during data reduction. Calibrated trihedral corner reflectors were deployed within each scene to permit absolute radiometric calibration of the image data. Initial analyses of this comprehensive radar data set is reported, with emphasis on implications for interpretation of Magellan data

Direct observation of twist mode in electroconvection in I52

I report on the direct observation of a uniform twist mode of the director field in electroconvection in I52. Recent theoretical work suggests that such a uniform twist mode of the director field is responsible for a number of secondary bifurcations in both electroconvection and thermal convection in nematics. I show here evidence that the proposed mechanisms are consistent with being the source of the previously reported SO2 state of electroconvection in I52. The same mechanisms also contribute to a tertiary Hopf bifurcation that I observe in electroconvection in I52. There are quantitative differences between the experiment and calculations that only include the twist mode. These differences suggest that a complete description must include effects described by the weak-electrolyte model of electroconvection

Using Fast Weights to Deblur Old Memories

Connectionist models usually have a single weight on each connection. Some interesting newproperties emerge if each connection has two weights: A slowly changing, plastic weight which stores long-term knowledge and a fast-changing, elastic weight which stores temporary knowledge and spontaneously decays towards zero. If a network learns a set of associations and then these associationsare "blurred" by subsequent learning, all the original associations can be "deblurred" by rehearsing on just a few of them. The rehearsal allows the fast weights to take on values that temporarily cancel outthe changes in the slow weights caused by the subsequent learning