Papers by Juan de Dios Ortuzar
Transportation, Nov 20, 2015
We provide an in-depth theoretical discussion about the differences between attitudes and percept... more We provide an in-depth theoretical discussion about the differences between attitudes and perceptions, as well as an empirical exercise to analyze its effects. This discussion is of importance, as the large majority of papers considering attitudinal latent variables, just consider those as attributes affecting directly the utility of a certain alternative while systematic taste variations are rarely taken into account and perceptions are normally completely ignored. The results of our case study show that perceptions may indeed affect the decision making process and that they are able to capture a significant part of the variability that is normally explained by alternative specific constants. In the same line, our results indicate that attitudes may be a reason for systematic taste variations, and that a proper categorization of the latent variables, in accordance with the underlying theory, may outperform the customary assumption of linearity.
Transportation, Jul 11, 2022
En este trabajo se combina un modelo de elección discreta con un modelo de variables latentes a f... more En este trabajo se combina un modelo de elección discreta con un modelo de variables latentes a fin de estudiar la elección modal entre bus y tren para viajes interurbanos, utilizando un enfoque secuencial. La principal innovación de este estudio es la inclusión de atributos modales en el modelo de variables latentes. Otra contribución de este estudio es mostrar como los resultados pueden ser afectados arbitrariamente por el modelador según la normalización elegida del modelo de variables latentes. Este ultimo resultado arroja ciertas dudas sobre la utilidad de estos modelos para el análisis económico, en especial si estamos interesados en obtener disposiciones al pago y / o elasticidades.
International Journal of Transport Economics, Jun 1, 2008
Transportation Research Part A-policy and Practice, Aug 1, 2021
Abstract The factors influencing trip departure time are taking more importance in urban planning... more Abstract The factors influencing trip departure time are taking more importance in urban planning practice since congestion is increasingly being addressed by travel demand management (TDM) strategies. In this paper we formulate and estimate a joint travel mode-departure time model for commuting trips using combined revealed preference (RP) and stated choice (SC) data. The RP data considered nine alternative modes and up to 11 time periods, and the level-of-service data were obtained at an unusual level of precision using GPS measurements. The travel time, cost and cost divided by the wage rate coefficients were fairly similar in both the RP and SC environments, suggesting equal error variances for both datasets. The only parameters that differed between each type of data were those associated with the schedule delay early (SDE) and late (SDL) variables required by Small’s Scheduling Model. This may be due to the potentially different temporal perspectives between RP choices (longer term decisions) and SC decisions, arguably shorter term given the nature of the experiment and the context presented in it (implementation of a congestion charging policy and a flexible working-hours scheme). The models were used to forecast the impacts of a hypothetic congestion charging scheme in Santiago, showing that the schedule delay coefficients derived from the SC context produced a smoother and less-peaked temporal distribution of travel demand than the RP parameters.
Emerald Group Publishing Limited eBooks, Jan 29, 2013
Abstract Purpose – Departure time choice not only depends on the desire to carry out activities a... more Abstract Purpose – Departure time choice not only depends on the desire to carry out activities at certain times and places; it is a complex decision making process influenced by travel conditions, congestion levels, activity schedules, and external trip factors. To estimate departure time choice models capturing the factors influencing it in appropriate form, a complex data collection procedure allowing to obtain detailed input data from different sources and at different time periods is required. The main aim of this chapter is to describe and discuss the survey methodology we used in a time-of-day choice project, involving the collection of revealed preference (RP) and stated preference (SP) data to estimate hybrid discrete departure time choice models incorporating latent variables. Preliminary model results are also presented as an example. Methodology/approach – Data was obtained from 405 workers at different private and public institutions located in the centre of Santiago, Chile. The survey process had three different stages and used various collection methods (e-mail, web-page, and personal interviews at the workplace) in order to satisfy efficiency, reliability and cost criteria. The RP component survey design was based on the last origin-destination survey implemented in Santiago (i.e. a travel diary filled under an activity recall framework). Relevant level-of-service measures at different time periods were obtained from GPS data measured from instrumented vehicles in the public and private transport networks. A SP-off-RP optimal design considering dependence among attribute levels was also developed. Finally, several 1–7 Likert scale questions were included to incorporate the latent variables. Findings – The survey methodology described in this chapter represents a successful experience in terms of collecting high quality data, from different sources, with the aim of estimating appropriate time-of-day choice models. The data collection process was carried out in different stages, by means of web pages, email, and personal interviews. The data was further enriched with level-of-service attributes measured at different times of the day with unusual precision. Preliminary results reported in this chapter show that data obtained through this methodology are appropriate to model time-of-day choices. Originality/value of chapter – The novelty of the survey methodology described in this chapter is the collection of data of a different nature for time-of-day choice modelling through the integration of different collection techniques. Acquisition of very precise information about preferred departure/arrival times, level of service at different times of the day, detailed information about flexibility in schedules, employment information and attitudes towards departure times, should allow practitioners to estimate hybrid time-of-day choice models incorporating latent variables.
Transportation Research Part A-policy and Practice, Feb 1, 2021
Abstract Studying road pricing acceptability has become increasingly relevant. Even though the po... more Abstract Studying road pricing acceptability has become increasingly relevant. Even though the policy has been effective in reducing the growing levels of congestion in several cities by curbing the indiscriminate use of the car, it still faces an initial rejection among the population in general. We discuss this issue based on a comprehensive review and set out to define what could be an acceptable road pricing scheme for Santiago de Chile. For this purpose, we estimated a hybrid discrete choice model that allowed us to segment the population according to their attitudes toward the measure. The preferred road pricing scheme in Santiago would charge only for entrance to the smallest of three cordons, around the historic centre of the city, during either the morning (or morning and evening) rush hours, provided that revenues were used to enhance public transport in the city. Since this is different from the best technical solution, which would imply charging in the largest cordon area, we suggest testing the preferred scheme in a pilot trial, following international recommendations and successful previous cases.
Wine is a complex product. The preferences for it are not only highly heterogeneous throughout th... more Wine is a complex product. The preferences for it are not only highly heterogeneous throughout the population, but also susceptible to context. The objective of this study is to discover and measure these preferences, focusing on non-sensory attributes of wine. To identify the most relevant non-sensory attributes of wine, from the consumers’ standpoint, four sources were considered: existing literature, a Delphi survey (short questionnaire applied to wine marketing experts), 14 in-depth interviews to consumers and a web survey answered by 843 wine consumers. Not all sources were consistent on which attributes were the most important. Notably, consumers did not pointed out price as a relevant attribute on the web survey, even though several in-depth interviewed consumers mentioned it as a relevant. Six wine attributes were selected for inclusion in the choice experiment: grape variety, alcohol level, label design, recommendations, price and discounts. An efficient experimental design...
Handbook of Research Methods and Applications in Transport Economics and Policy
Travel Behaviour Research, 2001
Libro de Actas CIT2016. XII Congreso de Ingeniería del Transporte, 2016
This paper explores the potential role of social capital variables on the transport mode choice. ... more This paper explores the potential role of social capital variables on the transport mode choice. Traditionally travel behavior model included social capital as empowerment factor (i.e. social capital as substitute of financial capital) or as social network influence on travel choice. Only recently constraints of social capital are considered as factors influencing travel behavior (Swanen et al, 2015, Di Ciommo & Martens, 2015).This article will show both aspects of empowerments and constraints of social capital in a dynamic way stressing two dynamic aspects of social capital: the building up social capital and use of social capital. Both aspects are related with the value of time: when you are doing something for others ( i.e. Voluntary actions, pick up all family members, etc) you are loosing your time, and your mode choice will be oriented to saving time, therefore a private mode will be chosen, while when you are using your social capital benefit (somebody else is helping you), y...
Transportation Research Part A: Policy and Practice
Journal of Choice Modelling
Wine is a complex product. Preferences for it are not only highly heterogeneous throughout the po... more Wine is a complex product. Preferences for it are not only highly heterogeneous throughout the population, but also amply susceptible to context. The objective of this study is to discover and measure these preferences, focusing on a set of non-sensory attributes of wine. To identify the most relevant non-sensory attributes of wine, from the consumers’ standpoint we considered four sources: existing literature, a Delphi survey (applied to wine marketing experts), in- depth interviews and a web-page survey answered by fairly large sample of wine consumers. Not all sources were consistent on which attributes were the most important. Notably, consumers did not select price as a relevant attribute on the web survey, even though it had been considered relevant in the in-depth interviews. Finally, six wine attributes were selected for inclusion in a stated choice (SC) experiment: grape variety, alcohol level, label design, product recommendations, price and discounts. An efficient experim...
Trip departure time has become a more important theme in practice as urban congestion problems ar... more Trip departure time has become a more important theme in practice as urban congestion problems are increasingly addressed by travel demand management (TDM) strategies. In this paper, the authors formulate and estimate a joint mode-departure time choice model using combining revealed preference (RP) and stated choice (SC) data about commuting trips in Santiago. The information was gathered through a series of surveys (RP, SC and attitudinal survey) applied to some 500 commuters in the Santiago Metropolitan Area. The travel time, cost and cost divided by wage rate coefficients were fairly similar in both environments (RP and SC), while schedule delay (SD) penalties associated with early or late arrival to work differed between each data. The degree of flexibility that workers have to adjust their arrival time to work resulted to be statistically significant when interacted with SD terms, suggesting that the level of work flexibility indeed influences temporal choices. The use of diffe...
Transportation Research Record: Journal of the Transportation Research Board, 2020
A variety of different pedestrian performance or service indicators (PPSI), such as the pedestria... more A variety of different pedestrian performance or service indicators (PPSI), such as the pedestrian level of service (PLOS), or quality of service (QoS), have been developed to evaluate pedestrian infrastructure. Although modeling approaches vary (e.g., ordinal least squares, scoring system), the great majority use on-site measurable attributes, such as sidewalk width or adjacent traffic, to estimate the PPSI. However, most of these models have been developed without jointly considering objective and subjective variables and their interactions. This study had two objectives: (i) to develop a model that simultaneously uses objective and subjective variables to estimate the pedestrian perception of sidewalks’ QoS in Bogota, Colombia, and (ii) to identify the interactions between objective variables and pedestrian perceptions of sidewalk attributes. To do so, data was gathered from 1056 users of 30 sidewalks in the city and an Ordered Probit Multiple Indicator and Multiple Cause model w...
Journal of Choice Modelling, 2019
Abstract The huge increase in higher education coverage in many developing countries has gone han... more Abstract The huge increase in higher education coverage in many developing countries has gone hand-in-hand with an additional supply of private colleges and with the enrolment of low to middle-class students, previously excluded from a historically elitist education segment. The larger diversity of both “suppliers and consumers”, unseen a few years ago, calls for methodological approaches that recognize heterogenous tastes and eventually, to classify individuals into mutually exclusive groups, something that can improve the design of public policy. The importance of college choice in educational systems using voucher schemes, makes it relevant to know what are the main variables determining such choice and whether they differ among different groups. Chile, one of the countries with the most extensive voucher system in education, experienced a significant increase in higher education enrolment (over 250% over the last 15 years), and has faced fierce political controversy due to the high heterogeneity in college quality. We use a latent class choice model to capture differences between groups, an approach that performs significantly better than simpler models previously used in this area. We found that groups of individuals with different selection patterns exist, which could not be defined ex ante, and that those groups are not only differentiated by their income level but mainly, by how they performed at high school. From the different sensitivities to college characteristics such as cost, quality, and location, identifying these groups allows us to derive different policy prescriptions.
Transportation, 2018
Supplying public transport systems with high levels of service quality is fundamental for retaini... more Supplying public transport systems with high levels of service quality is fundamental for retaining users and attracting new ones. Policies that improve transit service quality will ultimately lead to more sustainable travel patterns. Measuring overall service quality implies measuring the quality of several specific attributes and is prevalently evaluated through the perceptions of users, using satisfaction rates. In this study, we demonstrate that there is a further element that can influence users' perceptions, the so-called critical incidents (CI), defined as encounters that are particularly satisfying or dissatisfying. The concept is not restricted to ratings of the predefined product or service attributes, because customers who experience CI remember them well and can usually describe the experience. We implement a framework that includes CI and is innovative for several reasons. Firstly, we introduce attribute-specific (e.g. reliability, safety, comfort) CI to explain attribute-specific satisfaction levels, and then we model these with latent constructs allowing for measurement error in recalling the CI. We also demonstrate that using an Ordinal-Probit approach leads to more accurate results than its numerical counterpart, the latter possibly presenting biased results. Finally, we present a full Structural Equation Multiple Cause Multiple Indicator (SEM-MIMIC) model, which corrects for heterogeneity in the perceptions of users regarding satisfaction with the various service attributes, with the overall service, and with loyalty. For these purposes, we analyse an extensive database (96,763 interviewed passengers) derived from Customer Satisfaction Surveys in the railway services offered in the hinterland of Milan. Our main contribution to the literature is that we show that the occurrence of a CI has a substantial negative impact on passenger satisfaction for all service attributes. As it is a policy-related variable, it can be managed directly by the public transport (PT) administrators. To better plan and improve PT services, avoiding CI in specific items should be the strategy to follow. On the other hand, reliability, and addedvalue services are the primary service attributes that have a positive effect on satisfaction with the overall service and, in turn, on loyalty. Our model can be useful for PT administrators as it sheds light on how to improve the service according to users' preferences, and by considering the differences among user categories.
Transportation Research Part A: Policy and Practice, 2019
This study aims to celebrate the first half century of the journal through a bibliometric study o... more This study aims to celebrate the first half century of the journal through a bibliometric study of the publications on all six parts between 1967 and 2016. It uses the most reliable database for academic research, the Web of Science Core Collection, to identify the leading trends in all TR journals in terms of impact, topics, authors, universities, and countries. Moreover, it uses the Visualization of Similarities (VOS) viewer software to analyse bibliographic coupling, co-citation, citation, co-authorship, and co-occurrence of keywords.
Research in Transportation Economics, 2016
Fare evasion is a problem in many public transport systems around the world. Policies to reduce t... more Fare evasion is a problem in many public transport systems around the world. Policies to reduce this problem are generally aimed at improving control systems and increasing fines for offenders. In this paper, we attempt to identify the joint impact of different variables explaining fare evasion using an econometric study. The variables found to be statistically significant are the level of inspection, the proximity to a Metro or intermodal station, the bus occupancy level, the period of the day, the geographic location and number of passengers boarding and alighting at each bus stop, among others. We propose a novel approach to perform cost-benefit evaluation in order to help authorities increase the costeffectiveness of ticket inspection strategies on a given time horizon. We obtain new evidence that indicates that inspection strategies can be cost-effective even when evaders are not given a fine.
Uploads
Papers by Juan de Dios Ortuzar