Stochastic efficiency analysis with risk aversion bounds: a correction

A recent paper by Hardaker et al. (The Australian Journal of Agricultural and Resource Economics, 48, 2004a, 253) and book by Hardaker et al. (Coping with Risk in Agriculture, 2004b) describe a procedure for determining an efficient set from among a set of random alternatives. This procedure, called stochastic efficiency with respect to a function (SERF), is claimed to make the same assumption concerning the risk aversion measures as does stochastic dominance with respect to a function (SDRF). This is claim is incorrect. SERF imposes an additional requirement on the risk aversion measures of the decision makers. Both procedures assume a lower and an upper bound on risk aversion, but SERF also assumes that all risk aversion measures are of the same functional form as these lower and upper bound functions. This additional strong requirement on risk preferences implies that the efficient set identified under SERF is usually smaller than that identified using SDRF.     

A diffusion model with application to evolving medical technologies

This paper reports on a system dynamics simulation model which was developed to study the diffusion of medical technologies but which should be applicable to other sorts of technologies as well. The model addresses both the adoption and the changing extent of use of an evolving, product-based technology and also endogenously accounts for changes in actual and perceived performance. Two specific medical case studies provide background to the model and are used for testing the model's ability to reproduce various aspects of historical behavior. The model's relatively complex structure is presented in the form of influence diagrams showing major flows and relationships. The paper concludes with a discussion of contributions and possible future uses and modifications of the model.     

On a family of data-based transformed models useful in forecasting technological substitutions

This paper examines, via real data, some well known models for technology substitution analysis. We propose a family of data-based transformed models that will include the models under examination as special cases. The basic thrust of the paper is the recognition that for technology substitution analysis, the observations are time series data and hence are not independent. Also, the functional form of the model should be determined by both theoretical considerations as well as the data on hand. This suggests that the traditional ordinary least squares procedure used in estimating the parameters and the resulting forecasting procedures are not adequate. The existing models examined here are Fisher–Pry, Gompertz, Weibull, and Normal. We stress the statistical aspects of the models and their relative merits in terms of predictive power. The criteria used for the purpose of comparison are the mean squared deviation and the mean absolute deviation of the predicted values compared with the actual observations.     

The effect of real rates of interest on housing prices

During the late 1970s, U.S. house prices were appreciating rapidly even though mortgage interest rates were climbing. Recently, interest rates have eased but prices have moderated. This study examines the role of appreciation expectations in overcoming the negative effects of nominal mortgage interest rates on house prices. Expectations of future appreciation are important determinants of house sales prices, remaining influential during periods of declining and moderating real prices, not just when prices are rising. The real rate of interest, as viewed by the homebuyer, is the mechanism for affecting change in housing price levels. Because the nominal interest rate is slow to reflect changes in expectations, these real rates vary over time. This ebb and flow of real interest rates appears to explain market price levels. Nominal rates play a role as well, primarily in the formation of appreciation expectations.     

INVESTMENT PERFORMANCE OF COMMON STOCKS IN RELATION TO INSIDER OWNERSHIP

In this paper, the authors empirically examine whether corporations with high degrees of insider ownership enjoy superior returns compared with firms with more diffuse ownership. In addition, the authors evaluate the effects of insider ownership on security returns in relations to the well-known effects of size and earnings yield (or price-earnings) ratios. Results indicate that, in addition to Basu's price-earnings effect, insider ownership is a new statistically significant variable that is associated with abnormal returns. This return anomaly might occur because the market pays an inadequate price for top managements' equity ownership, a firm-specific fundamental variable that has a theoretical foundation in agency theory.     

Cross-Hedging: Basis Risk and Choice of the Optimal Hedging Vehicle

The basis between a futures contract and its underlying instrument is an important measure of the cost of using the futures contract to hedge. In a cross-hedge, the relative size of the basis of alternative hedging vehicles often plays a decisive role in the selection of the optimal hedging vehicle. After adjusting hedge ratios for basis risk, a genuine risk-cost trade-off is seen in hedging 90-day certificates of deposit with either the Treasury bill contract or the Eurodollar contract. The Eurodollar contract was not uniformly superior as generally believed.