Stated & Revealed Preference
As part of our specialist transportation activities, we are one of the few consultancies expert in undertaking stated preference (SP) market research for clients and are at the forefront of the development of new SP experimentation techniques. The consultancy's principal is an international expert on SP.
SP provides a realistic method of forecasting the demand for a new mode of transport. It can be used to forecast future travel choice and to design for a more sustainable transport system in the future. Augmented by other market research methods, it can provide much deeper insight into travel behaviour. It is particularly suitable for developing public transport solutions for Local Transport Plans.
Attitudinal market research can produce misleading results in situations where people may say one thing, but do something quite different. SP can be used to cut through this problem by offering travel choices to a structured statistical design.
Key to the success of SP is the need to make the SP game relevant to each individual respondent with properly structured computer-based interviewing. We are at the leading edge in this field offering individually tailored questionnaires and SP games, computer graphics, databases, algorithms and even transport models within the questionnaire.
We have developed our Visual Choice Modelling software to undertake statistical SP design and coefficient estimation using the logit model with maximum likelihood (including multinomial, nested, cross nested, mixed and latent class logit). They can be used for revealed preference (RP), SP or hybrid estimations with orthogonal fractional factorial or efficient designs. Visual Choice is state-of-the-art and is marketed internationally.
We have undertaken over forty key SP projects for clients: to develop a public transport strategy for Kent including road pricing and parking tariffs, for park and ride in Truro, for developing international air services from Scotland, for Eurotunnel's demand and revenue forecasts and for British Rail's product and pricing strategy. We have been responsible for demand modelling for several important LRT schemes. We measured the perceived valuation of 12 different attributes of quality buses for Centro including some very qualitative ones. We also used SP in conjunction with the development of market models to identify potential international air services from Scotland and in another study to develop a national toll road strategy for Morocco.