Bayesian estimation of willingness-to-pay where respondents mis-report their preferences

We introduce a modified conditional logit model that takes account of uncertainty associated with mis-reporting in revealed preference experiments estimating willingness-to-pay (WTP). Like Hausman et al. [Journal of Econometrics (1988) Vol. 87, pp. 239-269], our model captures the extent and direction of uncertainty by respondents. Using a Bayesian methodology, we apply our model to a choice modelling (CM) data set examining UK consumer preferences for non-pesticide food. We compare the results of our model with the Hausman model. WTP estimates are produced for different groups of consumers and we find that modified estimates of WTP, that take account of mis-reporting, are substantially revised downwards. We find a significant proportion of respondents mis-reporting in favour of the non-pesticide option. Finally, with this data set, Bayes factors suggest that our model is preferred to the Hausman model.

An analysis of verbal responses to music in a group of adult non-specialists

In a workshop setting, two pieces of recorded music were presented to a group of adult non-specialists; a key feature was to set up structured discussion within which the respondents considered each piece of music as a whole and not in its constituent parts. There were two areas of interest, namely to explore whether the respondents were likely to identify the musical features or to make extra-musical associations and, to establish the extent to which there would be commonality and difference in their approach to formulating the verbal responses. An inductive approach was used in the analysis of data to reveal some of the working theories underpinning the intuitive musicianship of the adult non-specialist listener. Findings have shown that, when unprompted by forced choice responses, the listeners generated responses that could be said to be information-poor in terms of musical features but rich in terms of the level of personal investment they made in formulating their responses. This is evidenced in a number of connections they made between the discursive and the non-discursive, including those which are relational and mediated by their experiences. Implications for music education are considered.

Stated attribute non-attendance in successive choice experiments

Attribute non-attendance in choice experiments affects WTP estimates and therefore the validity of the method. A recent strand of literature uses attenuated estimates of marginal utilities of ignored attributes. Following this approach, we propose a generalisation of the mixed logit model whereby the distribution of marginal utility coefficients of a stated non-attender has a potentially lower mean and lower variance than those of a stated attender. Model comparison shows that our shrinkage approach fits the data better and produces more reliable WTP estimates. We further find that while reliability of stated attribute non-attendance increases in successive choice experiments, it does not increase when respondents report having ignored the same attribute twice.

Joint use of attribute importance rankings and non-attendance data in choice experiments

The joint and alternative uses of attribute non-attendance and importance ranking data within discrete choice experiments are investigated using data from Lebanon examining consumers’ preferences for safety certification in food. We find that both types of information; attribute non-attendance and importance rankings, improve estimates of respondent utility. We introduce a method of integrating both types of information simultaneously and find that this outperforms models where either importance ranking or non-attendance data are used alone. As in previous studies, stated non-attendance of attributes was not found to be consistent with respondents having zero marginal utility for those attributes