A Note on the Variability of V538 Cassiopeiae

CCD observations of V538 Cas have been made on nine nights during three weeks using the AAVSO Bright Star Monitor. No significant variations were found.Comment: To be published in The Journal of the American Association Of Variable Star Observers (JAAVSO

Banking and the Determinants of Credit Crunches

Why do banks suddenly tighten the criteria needed for credit? Credit crunches are often explained by the implementation of new regulatory rules or by sudden drops in firm quality. We present a novel model of an artificial credit market and show that crunches have a tendency to occur even if firm quality remains constant, as well as when there are no new regulatory rules stipulating lenders capital requirements. We find evidence in line with the asset deterioration hypothesis and results that emphasise the importance of accurate firm quality estimates. In addition, we find that an increase in the debts’ time to maturity reduces the probability of a credit crunch and that a conservative lending approach is intrinsically related to the onset of crunches. Thus, our results suggest some up till now partially overlooked components contributing to the financial stability of an economy.lending; screening; agent based model; financial stability

Error Corrected Disequilibrium

We derive an econometric disequilibrium model for time series data. This is done by error correcting the supply of some good. The model naturally separates between a continuously clearing market and a clearing market in the long-run such that we are able to obtain a novel test of clearing markets. We apply the model to the Swedish market for short-term business loans, and find that this market is characterized by a long-run non-market clearing equilibrium.disequilibrium econometrics; error correction; clearing market; interest rates; credit market

The Credit Market and the Determinants of Credit Crunches: An Agent Based Modeling Approach

This paper presents a credit market model and finds, using an agent based modeling approach, that credit crunches have a tendency to occur; even when credit markets are almost entirely transparent in the absence of external shocks. We find evidence supporting the asset deterioration hypothesis and results that emphasize the importance of accurate firm quality estimates. In addition, we find that an increase in the debt’s time to maturity, homogenous expected default rates and a conservative lending approach, reduces the probability of a credit crunch. Thus, our results suggest some up till now partially overlooked components contributing to the financial stability of an economy.financial stability; banking; lending; screening; truncation

White dwarfs and Galactic dark matter

We discuss the recent discovery by Oppenheimer et al (2001) of old, cool white dwarf stars, which may be the first direct detection of Galactic halo dark matter. We argue here that the contribution of more mundane white dwarfs of the stellar halo and thick disk would contribute sufficiently to explain the new high velocity white dwarfs without invoking putative white dwarfs of the dark halo. This by no means rules out that the dark matter has been found, but it does constrain the overall contribution by white dwarfs brighter than M_V ~ 16 to significantly less than 1% of the Galactic dark matter. This work confirms a similar study by Reyle et al (2001).Comment: 8 pages, 8 figures. MNRAS style fil

The Supply Function Equilibrium and Its Policy Implications for Wholesale Electricity Auctions

The supply function equilibrium provides a game-theoretic model of strategic bidding in oligopolistic wholesale electricity auctions. This paper presents an intuitive account of current understanding and shows how welfare losses depend on the number of firms in the market and their asymmetry. Previous results and general recommendations for divisible-good/multi-unit auctions provides guidance on the design of the auction format; setting the reservation price; the rationing rule; and restrictions on the offer curves in wholesale electricity auctions.Wholesale Electricity Markets; Supply Function Equilibria; Competition Policy