Additive and Multiplicative Uncertainty Revisited: What Explains the Contrasting Biases?

above the certainty level while for additive uncertainty the price should be lower than the certainty level. This note gives an intuitive explanation for the result after first presenting a parsimonious review of the two models. We also discuss which, if either, of the two models is more realistic. Received December 14, 2001; revised version received July 16, 2002 Published online: April 30, 2003 We thank referees for helpful comments. Ciaran Driver would like to acknowledge the research facilities from ANU, Canberra for their help in writing this paper.     

Choice of utility function form: its effect on classification of risk preferences and the prediction of farmer decisions

In applications of expected utility analysis, researchers are confronted with a choice among several utility functional forms. Subjective utility values and probability distributions for price and yield were elicited from Sri Lankan producers of minor export crops. Exponential quadratic and cubic utility functions were estimated. The choice of functional form was found to affect both the classification of risk attitudes and the prediction of harvesting strategy. The exponential function was the best predictor of harvesting strategy because it was the best predictor of mature harvesting. All three functions were equally poor predictors of premature harvesting.     

iTV: A major opportunity for financial services,or not?

Interactive television has arrived, thanks to substantial technology investments that have been made by Sky and others. It is growing in importance as innovative interactive applications are developed for broadcast programmes (eg the BBCi service and Big Brother), and for advertising — and will develop further when broadband deployment gets to critical mass. Readers should not expect a television-variant of the world wide web, however. This was tried during 2000–2002 in the form of web look-alike, interactive ‘walled garden’ sites, and failed to attract critical mass footfall. The model has evolved and now revolves around interactive content synchronised with broadcast, which offers financial services companies an interesting new way to increase awareness and to differentiate the service presentation. Furthermore, over the next ten years, broadband is expected to usher in a new era of personalised television — in which specialised broadcasts (such as personal pensions advice programmes) can be made available on demand. The observations in this paper are mainly drawn from the UK, where digital television penetration is high; the lessons can be applied more broadly, however, and are relevant to any organisation thinking of promoting its service through entertainment channels.     

Interannual Climate Variation, Climate Prediction, and Agricultural Trade: the Costs of Surprise versus Variability

Agriculture remains sensitive to variation in rainfall and temperature. Fortunately, our ability to predict the lower frequency variation in the earth's atmosphere is increasing rapidly. While information cannot affect the underlying source of variability, it allows unexpected shocks to be anticipated and acted upon. This paper develops and analyzes an intertemporal Ricardian trade model with Bayesian beliefs. Results in this paper show that improved climate prediction reduces expected prices, but increases price variability. In addition, trade is crucial to realizing the potential benefits of climate prediction. The value of climate prediction is highest with both storage and trade, and falls by over 300% when a country is in autarky.