Efficient choice set designs for estimating availability cross-effects models

Batsell and Polking proposed a discrete choice model which incorporates the availability (presence or absence) of competing brands into the utility of each brand under study. The information on relative impacts of adding or deleting brands is of strategic interest, and models that do not incorporate such effects may be misleading. The designs suggested by Batsell and Polking have 2^m–m–1 choice sets. Even with as few as 10=m brands, this requires over 1000 choice sets. In this paper we provide a catalog of designs for estimating cross effects models in as few as 2m–1 choice sets. This will make cross effects modelling practical in a wide range of academic and commercial settings.     

On forecasting interest rates: An efficient markets perspective

Efficient markets do not preclude economic agents from successfully forecasting movements in short-term interest rates. For brief forecast intervals, however, ex ante changes in long-term rates are sufficiently close to zero that economic agents are not likely to improve upon the no-change prediction of the martingale model. Economic agents, in effect, are not likely to succeed in forecasting short-term movements in long-term interest rates. This paper illustrates the closeness of the martingale approximation for two sets of Canadian interest rates data, emphasizing the importance of the forecast interval. The paper then examines three sets of recorded forecasts of Canadian interest rates and finds results consistent with the theoretical discussion.     

A comparison of the Box-Cox maximum likelihood estimator and the non-linear two-stage least squares estimator

This paper investigates the limiting behaviour of the ‘maximum likelihood estimator’(MLE) based on normality, as well as the nonlinear two-stage least squares estimator (NL2S), for the i.i.d. and regression models in which the Box-Cox transformation is applied to the dependent variable. Since the transformed variable cannot in general be normally distributed, the untransformed variable is assumed to have a two-parameter gamma distribution. Tables of probability limits and asymptotic variance demonstrate that, in this case, the inconsistency of the ‘normal MLE’ is often quite pronounced, while the NL2S is consistent and typically well behaved.