The role of perceived acceptability of alternatives in identifying and assessing choice set processing strategies in stated choice settings: The case of road pricing reform

In designing choice experiments, it is common to present a number of alternatives to a respondent and have them choose the most preferred alternative. However, respondents may ignore one or more alternatives which they deem unacceptable for various reasons. This possibility aligns with the idea of the ‘consideration set’ which influences the choice of an alternative given the choice set of interest. This paper uses an endogenous choice set model to investigate the influence that contextual effects and socioeconomic characteristics play in explaining variations in the choice sets considered by respondents when they reveal their preferences.     

Analyzing discrepancies between willingness to pay and willingness to accept for freight transport attributes

In this paper we use discrete choice data to analyze asymmetries in the preference for freight transport attributes. A reference dependent utility specification allowed us to test for the existence of substantial asymmetries in perception of the transport cost. Hence, the re-estimation of our models in the WTP/WTA space helped us to quantify significant discrepancies between the WTP and WTA for the attributes included in the choice experiment, namely transit time, service frequency and delays in delivery time. Results are deemed essential to define alternative services to road capable to attract substantial volumes of freight.     

Experience conditioning in commuter modal choice modelling – Does it make a difference?

This paper investigates the impact of decision maker’s experience on model elasticities and predicted market share, using data collected in Sydney on commuter mode choice. Usage frequency is used as a proxy for experience and two separate mode choice models are estimated – one with experience conditioning choice and one without. Key model outputs are compared and we find that differences in the value of travel time savings and model elasticities are very marked. This suggests that ignoring experience that one has with each alternative in their choice set may be a candidate source of error in travel demand forecasts. We develop a method to obtain the level of experience for use in application of choice models to increase their prediction power.     

Dissecting preference heterogeneity in consumer stated choices

This paper investigates alternative methods to account for preference heterogeneity in choice experiments. Heterogeneity can be explained by assuming its influence to impact the systematic component of utility, the stochastic one or both. Seven different models were estimated to search for heterogeneity along the three dimensions described. The comparison based on model performance and willingness to pay measures shows that methods to search for heterogeneity are not independent one from the other and might produce substantially different results giving rise to different policy implications.     

Recovering costs through price and service differentiation: Accounting for exogenous information on attribute processing strategies in airline choice

The entry of low cost airlines has thrown out a challenge to all airlines to find ways of attracting passengers, through a mix of fare discounting, greater frequency, improved flight times and no-frill's levels of on-board service. These competitive strategies have an impact on cost recovery. As airlines seek business in an increasingly heterogeneous passenger market, a greater understanding of what matters to potential passengers in choosing an airline grows in importance. Traditional studies of passenger airline choice assume that all attributes matter, but some to a lesser extent. What happens to the empirical evidence on willingness to pay when specific attributes are totally ignored by particular passengers? In this paper, we examine the impact of individual-specific attribute processing strategies (APS) on the inclusion/exclusion of attributes on the parameter estimates and behavioural outputs of models of airline service and fare level choice. Modelling practice assumes that whilst respondents may exhibit preference heterogeneity, they employ a homogenous APS with regards to how they process the presence/absence of attributes of stated choice (SC) experiments. We demonstrate how information collected exogenous of the SC experiment on whether respondents either ignored or considered each attribute of the SC task may be used in the estimation process, and how such information may be used to provide outputs that are attribute processing strategies segment specific.     

Customer perspective on overbooking: The failure of customers to enjoy their reserved services,accidental or intended?

Overbooking is widely applied in the service industry to hedge against undesirable situations, such as cancellations and no-shows. However, during the implementation of overbooking, service providers may turn down some customers when the number of arrivals exceeds their capacity on the target date. Therefore, this paper examines overbooking from the customers' perspective to offer them a clear perception on the possibility for their reservations to be denied by the service provider. By establishing a Stackelberg model between a service provider and an online travel agency, we explore how optimal overbooking strategy is developed by the service provider. Afterward, by analyzing the obtained optimal overbooking pad, we calculate the probabilities of denied service under different levels of monetary compensation that is paid to denied customers. A higher monetary compensation guarantees a higher chance of successful service. This paper also provides customers with some reference when booking services.     

The use of mixtures of market and experimental choice data in establishing guideline weights for evaluating competitive bids in a transport organisation

The government sector is increasingly using competitive bidding for service deliveries such as the provision of bus and rail services as well as the purchasing of professional engineering services such as project planning, design, and project supervision. As part of a program to simplify and introduce consistency in the tender evaluation process, one government transport agency in New Zealand financed a study to investigate the potential of combined revealed and stated preference methods as a way of establishing weights to attach to the criteria used to evaluate offers of engineering services. These techniques have mainly been used in the study of travel choices; yet they have a much broader appeal in studying the decision making process of organisations. In this paper we use a data-mixing model to capture the decision expertise of a transport organisation through the revelation of preference weights for each evaluation criterion. Using choice information based on both market-driven and experimentally derived choice sets, we should be able to increase the robustness of the evaluation weights in comparison to the weights obtained from single data-sourced models. The resulting parameterised tool can be used in subsequent tender evaluations to provide an additional source of advice to supplement or replace that provided by current members of a bid evaluation team.     

UK supply chain carbon mitigation strategies using alternative ports and multimodal freight transport operations

In the last few decades, the building evidence that CO₂e emissions lead to climate change has pointed to a need to reduce CO₂e emissions. This research uses five scenarios in the context of UK import trade to assess total CO₂e emissions and costs of import re-routing containers. The overall objective is to assess possible carbon mitigation strategies for UK supply chains by using a combination of alternative ports and revised multimodal strategies. The model adopted includes three elements: port expansion, container handling and freight transport. The alternative scenarios explore different settings modal shift and short sea shipping.     

A network-based analysis of the impact of structural damage on urban accessibility following a disaster: the case of the seismically damaged Port Au Prince and Carrefour urban road networks

The magnitude 7.0 earthquake that struck Haiti in January 2010 led to an unprecedented effort in collecting and providing geographical information in support of humanitarian aid. Although most of the compiled datasets and generated maps were able to provide specific and detailed information regarding the location of damaged buildings and road interruptions, none or little information was available to describe the accessibility—or otherwise—of the urban space. Here we try to offer an alternative method to define the urban accessibility landscape in the aftermath of earthquake damage, by combining simple graph theory concepts and GIS-based spatial analysis to assess how the urban space accessibility decreases when the road network is damaged.     

A border effect in airport choice: Evidence from Western Europe

Some commentators suggest that air travelers are reluctant to use a foreign airport as a point of departure for their journey. Such reluctance has implications for marketing and policy measures, especially in border regions and in smaller countries, such as the Netherlands and Belgium. In this study, we tested this supposed barrier effect of national borders with empirical data.Our research is based on a subsample (n = 4083) of a large-scale survey among German, Dutch and Belgian adults. Participants were asked about their most recent flight, preferences regarding long-distance travel, and general travel behavior. The survey information about the most recent trip was linked to the Official Airline Guide with data from 18 airports in the Western European region. On average, however, only 10 airports offered a direct connection to the destination of the respondents’ most recent flight. A conditional logit model with varying choice sets allowed us to model only the relevant airports per respondent, while accounting for other known determinants in airport choice, such as travel time, airline competition, and number of available flights.The model results confirmed our expectations: people strongly prefer a departure airport situated in their own country. The model predictions suggest that without the border effect the share of people in our sample departing abroad would rise from 7.7% to 18.7%. Experience (with multiple airports as a point of departure) mitigates the barrier effect of the border. The performance of our model is good: the median probabilitie for the chosen alternative is 68%. Our research stresses the importance of the barrier effect of borders in airport choice: even when traveling across borders in the European sky, national borders remain important.     

The role of attribute processing strategies in estimating the preferences of road freight stakeholders

Choice behaviour studies typically assume passive bounded rationality, suggesting that decision makers process all information given to them with equal attention. However, it is probable that decision makers invoke any number of attribute processing strategies (APSs) when weighing the characteristics of candidate alternatives against one another. Utilising data from a study of urban road freight stakeholders evaluating alternative packages of component trip times, fuel costs and variable user charges, this paper shows that accounting for APS heterogeneity associate with each alternative in each choice set results in differing marginal disutilities and willingness to pay for components of travel time, compared to a model which assumes passive bounded rationality.     

The problematic nature of sustainable tourism: some implications for planners and managers

Sustainability is a principle and practice expected of tourism development and management. The uneven performance of sustainable tourism policies and strategies is generating increasing attention and concern, along with a need to better understand sustainability and the problems it presents tourism planners and managers. In this article, we investigate the notion that traditional tourism problem-solving paradigms and approaches are not effective for all of the problems arising in sustainable tourism and explore what new approaches may be required. After a brief, but necessary definition of key concepts, we take a look at the range of problems which can arise in sustainable tourism and review what research has to offer in terms of understanding why some of these problems seem resistant to traditional problem-solving approaches. Following that, we consider the problems of sustainable tourism through a series of three analytical lenses, the Cynefin Framework, Complexity Science and Wicked Problems, to explore what would be required to address the more intractable problems of sustainable tourism. Examples of problems from sustainable tourism are used to illustrate how each analytical lens frames problems, incorporates stakeholder perspectives, and identifies alternative causes, processes and outcomes of problems. We conclude with implications for both theory and practice.     

Accommodating spatial correlation across choice alternatives in discrete choice models: an application to modeling residential location choice behavior

This paper presents a modeling methodology capable of accounting for spatial correlation across choice alternatives in discrete choice modeling applications. Many location choice (e.g., residential location, workplace location, destination location) modeling contexts involve choice sets where alternatives are spatially correlated with one another due to unobserved factors. In the presence of such spatial correlation, traditional discrete choice modeling methods that are often based on the assumption of independence among choice alternatives are not appropriate. In this paper, a Generalized Spatially Correlated Logit (GSCL) model that allows one to represent the degree of spatial correlation as a function of a multi-dimensional vector of attributes characterizing each pair of location choice alternatives is formulated and presented. The formulation of the GSCL model allows one to accommodate alternative correlation mechanisms rather than pre-imposing restrictive correlation assumptions on the location choice alternatives. The model is applied to the analysis of residential location choice behavior using a sample of households drawn from the 2000 San Francisco Bay Area Travel Survey (BATS) data set. Model estimation results obtained from the GSCL are compared against those obtained using the standard multinomial logit (MNL) model and the spatially correlated logit (SCL) model where only correlations across neighboring (or adjacent) alternatives are accommodated. Model findings suggest that there is significant spatial correlation across alternatives that do not share a common boundary, and that the GSCL offers the ability to more accurately capture spatial location choice behavior.     

On structural inelasticity of modal substitution in freight transport

At the European level there is an increasing focus on how freight transport can be moved from trucks on roads to more environmentally friendly modes such as rail and ship. A large proportion of the transport services between OD pairs, however, cannot be substituted since there is only one alternative available. The paper investigates the magnitude of this “structural inelasticity” of modal substitution in freight transport due to a sparser layout of rail and ship-based freight networks compared to road. In the analysis we use a recent Scandinavian freight demand model covering more than 800 zones. We find that the structural inelasticity is very significant - in particular for transportation over less than 500 km. Moreover, the inelasticity varies greatly with commodity groups and between OD pairs, and it depends strongly on the port and rail infrastructure. The results suggest that pure charging instruments (road pricing for trucks) in many regions will have limited mode substitution impacts. However, if combined with structural changes in terms of improved infrastructure for rail and ship, impacts may be greater.     

Do satisfying walking and cycling trips result in more future trips with active travel modes? An exploratory study

Previous studies have indicated that travel satisfaction - the experienced emotions during, and cognitive evaluation of, a trip - can be affected by travel mode choice and other trip characteristics. However, as satisfactory trips might improve a person's attitude towards the used mode, persons may be more likely to use that same mode for future trips of the same kind. Hence, a cyclical process between travel mode choice and travel satisfaction might occur. In this paper we begin to analyse this process—using a structural equation modelling approach on cross-sectional data—for people who engage in walking and cycling for leisure trips in the Belgian city of Ghent. The focus on walking and cycling reflects recent studies indicating that active travel is often associated with the highest levels of travel satisfaction. Results of this exploratory analysis offer tentative support for the idea of a cyclical process: the evaluation of walking and cycling trips positively affects the respondents' attitude towards the respective mode, which in turn has a positive effect on choosing that mode.     

Student’s vacation travel: A reference dependent model of airline fares preferences

This article reports the results of student vacation travel choice analysis using a reference dependent model of airline fare preferences. Findings suggests, as expected, that the preferences/utility decreases with increasing levels of cost. The evaluation of the airfare, however, becomes significantly more critical in the regime were low-fare airlines are more expensive than the regular airlines, meaning that price sensitivity for low-fare airlines is higher in this case. Part-worth utility functions for airfare as part of a more general portfolio model of vacation decisions of students suggest that indeed a reference dependent model captures such regimes in utility space.     

Welfare calculations in discrete choice settings: An exploratory analysis of error term correlation with finite populations

A difference in logsum terms (also known as inclusive values) is becoming a standard practice for anticipating the welfare impacts of transport policy when choice alternatives are discrete and behavior is (assumed to be) random-utility maximizing. However, this calculation is only an approximation when the population under study is finite. This paper examines the effect of error term correlations in such welfare analyses with finite samples, recognizing that individual preferences and unobserved attributes influencing choice are unlikely to change much, if at all, across scenarios or across alternatives. Such measures appear reasonably robust to deviations in assumptions of correlation. Nevertheless, we identify cases when the synthetic population samples need to be quite large for the average logsum to be realized. Another finding in these results is the substantial variation that emerges across synthetic populations, suggesting that policies that appear welfare-improving (when evaluated with average welfare formulations) may well be welfare-reducing (or vice versa) for a wide variety of actual, finite populations.     

Valuation of travel time for international long-distance travel – results from the Fehmarn Belt stated choice experiment

The geographical scope of travel varies from short distances in urban areas to long distances across cities and countries. While urban travel has been widely analysed in the literature, travel over longer distances and particularly across countries, has received much less attention. While this may be justified due to the number of travellers it cannot be justified when looking at the mileage consumption and its resulting environmental impacts. In this paper, we investigate international long-distance travel preferences related to travel between Scandinavia and Central Europe with particular focus on the Fehmarn Belt fixed link between Germany and Denmark to be opened in 2021. To facilitate long-term demand forecasts for the future fixed link, stated preference data were collected in 2011. Based on these data a discrete choice model for long-distance travellers was developed in order to estimate the value of travel time savings (VTTS). The final model, which was formulated as a nested logit model and included Box–Cox transformed travel time and cost attributes, revealed several interesting findings. Firstly, we found damping effects in both cost and time – most strongly in cost. Secondly, we found significant interactions among travel cost and time, and journey characteristics, such as distance and duration. This had direct impact on the VTTS, which was shown to decrease with distance and duration. Thirdly, we found that air travel implies a higher average VTTS, which is to be expected but rarely supported by empirical evidence.     

Passenger airline choice behavior for domestic short-haul travel in South Korea

When the Seoul-Busan line of South Korea's high-speed rail system, dubbed the Korea Train Express (KTX), entered service in November 2010, it was expected that this line would compete with air transport services for short-haul domestic journeys. Therefore this is a study about passengers' choice behavior when traveling short-haul domestic routes in South Korea. It utilizes MNL and NL logit models with selected variables, and the data required for the analyses were gathered through Stated Preference (SP) Techniques. The main SP survey was conducted for three weeks at departure lounges in Incheon International Airport in May 2012. The results reveal that fare, access time and journey time are significantly important with respect to passenger choice. The results further indicate that business travelers are more willing to pay than non-business travelers to reduce access and journey time. It is also noteworthy that reducing access time is more important than reducing journey time for short-haul domestic travelers. The conclusion is that it is significantly important for airline planners or local authorities that want to increase their local market share to invest in relatively fast access modes.