As set out in Section 2, there is increasing interest in modelling the choice
processes undertaken by air travellers. Typically, these studies make use of
discrete choice models that allow analysts to relate observed or stated choices to
the attributes of the various alternatives that the respondents are faced with.
A major problem in the area of air travel choice behaviour research is the poor
quality of Revealed Preference (RP) data, leading to an inability to estimate
significant effects for a number of crucial attributes such as air fares. Similarly
however, the Stated Preference (SP) surveys used in the field of air transport
have generally not been able to do justice to the complexity of the choice
processes faced by air travellers.