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

Outcastes in an 'Egalitarian' Society: Tamang/Blacksmith Relations from Tamang Perspective

Occasional Papers in Sociology and Anthropology - Volume 10, 200

Game-theoretical, Strategic forward Contracting in the Electricity Market

Forward sales is a credible commitment to aggressive spot market bidding, and it mitigates producers’ market power in electricity markets. Still it can be profitable for a producer to make such a commitment if it results in a soft response from competitors in the spot market (strategies are substitutes). The optimal contracting level of a risk-neutral producer is determined by the extent to which strategies are substitutes and the slope of the residual demand in the forward market. Conditions under which strategies are substitutes are identified for a two-stage game with supply function competition and capacity constrained producers.Supply Function Equilibrium; Forward Market; Strategic Contracting; Arbitrage; Strategic Substitutes; Oligopoly; Electricity Market

Supply Function Equilibria of Pay-as-Bid Auctions

This paper characterizes the Nash equilibrium in a pay-as-bid (discriminatory), divisible-good, procurement auction. Demand by the auctioneer is uncertain as in the supply function equilibrium model. A closed form expression is derived. Existence of an equilibrium is ensured if the hazard rate of the perfectly inelastic demand is monotonically decreasing and sellers have non-decreasing marginal costs. Multiple equilibria can be ruled out for markets, for which the auctioneer’s demand exceeds suppliers’ capacity with a positive probability. The derived equilibrium can be used to model strategic bidding behaviour in pay-as-bid electricity auctions, such as the balancing mechanism of United Kingdom. Offer curves and mark-ups of the derived equilibrium are compared to results for the SFE of a uniform-price auction.Supply Function Equilibrium; Pay-as-bid Auction; Discriminatory Auction; Divisible

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

Unique Supply Function Equilibrium with Capacity Constraints

Consider a market where producers submit supply functions to a procurement auction — e.g. an electric power auction — under uncertainty, before demand has been realized. In the Supply Function Equilibrium (SFE), every firm commits to the supply function maximizing his expected profit given the supply functions of the competitors. The presence of multiple equilibria is one basic weakness of SFE. This paper shows that with (i) symmetric producers, (ii) inelastic demand, (iii) a reservation price, and (iiii) capacity constraints that bind with a positive probability, there is a unique symmetric SFE.Supply function equilibrium; auction; oligopoly; capacity constraint; wholesale electricity 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

The local density of matter mapped by Hipparcos

We determine the velocity distribution and space density of a volume complete sample of A and F stars, using parallaxes and proper motions from the Hipparcos satellite. We use these data to solve for the gravitational potential vertically in the local Galactic disc, by comparing the Hipparcos measured space density with predictions from various disc models. We derive an estimate of the local dynamical mass density of 0.102 +/- 0.010 solar masses per cubic parsec which may be compared to an estimate of 0.095 solar masses per cubic parsec in visible disc matter. Our estimate is found to be in reasonable agreement with other estimates by Creze et al. and Pham, also based on Hipparcos data. We conclude that there is no compelling evidence for significant amounts of dark matter in the disc.Comment: 9 pages, 7 figures, accepted by MNRA

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