| 1. |
- Andersson, Jan, 1965-, et al.
(författare)
-
The complexity of changes in modal choice : A quasi-experimental study
- 2023
-
Ingår i: Transportation Research Part F. - : Elsevier. - 1369-8478 .- 1873-5517. ; 96:July, s. 36-47
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Changes in modal choice is argued to be one way to reduce the emission of greenhouse gases. Increasing modal choices in favour of more environmentally friendly travel modes requires a better understanding of how these choices are actually made. The first aim of this study is therefore to examine how modal choice is related to subjective experiences as perceived accessibility, perceived satisfaction , habit, both before , after an intervention promoting public transport. The second aim is to examine how modal choice is affected by the intervention. Finally, the third aim is to examine how subjective experiences as perceived accessibility, perceived satisfaction, and habit are affected by the intervention.Method: The design used is a before-and after-study with free public travel passes as the intervention (30-or 14-days free travel pass). Altogether, 52 travelers - distributed on two intervention groups and one control group - participated in the study. The 30-days free travel pass group constitutes 18 participants, the 14-days free travel pass group constitutes 19 participants while the control group constitutes 15 participants. During the before -period the participants were asked to register their modal choice using a digitalized application downloaded on their smart phones (the TravelVu app), to complete a short app-based questionnaire, and a web-based questionnaire. During the after-period, they were once again asked to register their modal choice and to complete a web-based questionnaire. All data collected were analyzed by variance or correlation analyses using the change between before-and after period as the dependent variable.Conclusion: The intervention did not affect the modal choice or the subjective experiences. Over time, the participants did however increase their use of public transport and their cognitive evaluation of their everyday travel overall, while they decreased their use of car and became less reflective and less interested in trying out new alternative travel modes. These changes might be attributed to their participation in the present study.
|
|
| 2. |
- Bakhtiary, Mohammadreza, et al.
(författare)
-
A tree-based extended model to predict intention to speed for taxi drivers
- 2024
-
Ingår i: Transportation Research Part F. - : Elsevier. - 1369-8478 .- 1873-5517. ; 103, s. 190-200
-
Tidskriftsartikel (refereegranskat)abstract
- The need to predict and understand drivers’ intention to violate emphasizes the importance of developing a model based on the motives behind the action. This study aims to develop a model to predict a taxi driver’s intention to speed in an urban area using variables including psychological factors, demographic information, and exposure. Aggregate (factor-based) and disaggregate (item-based) models of input variables will also be compared. In this study, the self-reported data on Tehran taxi drivers was collected in the form of a scenario-based questionnaire which is inspired by the Theory of Planned Behaviour (TPB). The intention to commit violations was predicted and modelled using stepwise regression and decision tree regression models. The results, based on the stepwise regression model showed a higher value of fitting score for an item-based linear model (R2 = 0.695), but the final model using the tree-based regression presented a better fit for the factored model (R2 = 0.746) considering the cross-validated model with the lowest deviation criteria (RMSD = 0.26). Furthermore, in this model attitude made the greatest contribution to the prediction of intention. The results obtained from the two different modelling approaches showed that exposure and age did not have much effect on the models. A main advantage of the current study is that the variables were compared and refined in two stages of exploratory factor analysis and stepwise regression before being entered into the tree regression model. In addition, the results of the factor-based model were compared with the item-based model.
|
|
| 3. |
- Booth, Leon, et al.
(författare)
-
Experiences of older adults interacting with a shared autonomous vehicle and recommendations for future implementation
- 2022
-
Ingår i: Transportation Research Part F. - : ELSEVIER SCI LTD. - 1369-8478 .- 1873-5517. ; 90, s. 100-108
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: A recognised potential benefit of autonomous vehicles is increased mobility for older adults. However, this group is more apprehensive about adoption, which may hinder uptake. Shared autonomous vehicles (SAVs) represent a use case that may be especially relevant for older people due to emerging applications in retirement villages and similar precincts. However, little research has examined the SAV-related concerns of older adults and strategies to address them. This study used an exploratory approach involving SAV exposure to identify strategies that may increase older people's receptiveness to SAVs. Method: Older adults living in retirement villages (n = 63) were interviewed while interacting with an SAV to examine their needs, expectations, and concerns regarding SAVs. The interview data were coded and thematically analysed. Results: Participants recommended the following approaches to ensuring SAVs are useful and acceptable to older adults: providing physical accessibility for those with mobility impairments, comfortable and practical internal layouts, and operating SAVs on convenient routes at useful speeds. Strategies such as exposing older adults to SAVs in operation to encourage uptake and initially ensuring a human assistant is present were suggested methods of increasing receptivity. Discussion: The findings suggest older passengers are likely to share many of the same reactions to SAVs as the broader population, but with a stronger focus on issues relating to accessibility and the physical layout of the vehicles. The solutions to these issues suggested by the study participants may be useful for those designing SAVs for use in older people's settings and beyond.
|
|
| 4. |
- Bärgman, Jonas, 1972, et al.
(författare)
-
Methodological challenges of scenario generation validation: A rear-end crash-causation model for virtual safety assessment
- 2024
-
Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour. - 1369-8478. ; 104, s. 374-410
-
Tidskriftsartikel (refereegranskat)abstract
- Safety assessment of crash and conflict avoidance systems is important for both the automotive industry and other stakeholders. One type of system that needs such an assessment is a driver monitoring system (DMS) with some intervention (e.g., warning or nudging) when the driver looks off-road for too long. Although using computer simulation to assess safety systems is becoming increasingly common, it is not yet commonly used for systems that affect driver behavior, such as DMSs. Models that generate virtual crashes, taking crash-causation mechanisms into account, are needed to assess these systems. However, few such models exist, and those that do have not been thoroughly validated on real-world data. This study aims to address this research gap by validating a rear-end crash-causation model which is based on four crash-causation mechanisms related to driver behavior: a) off-road glances, b) too-short headway, c) not braking with the maximum deceleration possible, and d) sleepiness (not reacting before the crash). The pre-crash kinematics were obtained from the German GIDAS in-depth crash database. Challenges with the validation process were identified and addressed. Most notably, a process was developed to transform the generated crashes to mimic the crash severity distribution in GIDAS. This step was necessary because GIDAS does not include property-damage-only (PDO) crashes, while the generated crashes cover the full range of severities (including low-severity crashes, of which many are PDOs). Our results indicate that the proposed model is a reasonably good crash generator. We further demonstrated that the model is a valid method for assessing DMSs in virtual simulations; it shows the safety impact of shorter ‘longest’ off-road glances. As expected, ‘cutting away’ long off-road glances substantially reduces the number of crashes that occur and reduces the average delta-v. This work highlights the need to both a) thoroughly understand the process of generating virtual scenarios and b) have the tools to validate them. While more work to develop validation processes for scenario generation is needed across all levels of crash severity, the transform and other validation tools that were developed bring us one step closer to accurate validation methodologies.
|
|
| 5. |
|
|
| 6. |
- Friman, Margareta, 1970-, et al.
(författare)
-
Are we leaving some people behind? Travel autonomy, perceived accessibility, and well-being among people experiencing mental and physical difficulties
- 2023
-
Ingår i: Transportation Research Part F. - : Elsevier. - 1369-8478 .- 1873-5517. ; 98, s. 243-253
-
Tidskriftsartikel (refereegranskat)abstract
- This study focuses on the association between cognitive, medical, and physical difficulties; mental illness; travel autonomy; and perceptions of the possibilities of participating in desired daily activities; further, we examine their association with happiness and life satisfaction. We present and empirically test an integrated framework with travel autonomy, defined as the prerequisites, freedom, and possibility to travel the way one wants, at its core. We use web survey data (n = 1041) collected in Sweden in 2021. Using partial least squares structural equations, we find a valid and reliable model with travel autonomy as a distinct and reliable latent construct. Furthermore, travel autonomy yields significant paths to perceived accessibility, happiness, and life satisfaction, highlighting the importance of capabilities, independent travel, freedom, and possibilities in the overall construct of travel autonomy. Finally, mental illness plays an important role in how people rate their travel autonomy.
|
|
| 7. |
- Gao, Kun, 1993, et al.
(författare)
-
Revealing psychological inertia in mode shift behavior and its quantitative influences on commuting trips
- 2020
-
Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour. - : Elsevier BV. - 1369-8478. ; 71, s. 272-287
-
Tidskriftsartikel (refereegranskat)abstract
- The inertia effects stemmed from repeated past behavior have been investigated by both psychology and transportation studies because of its bearing on explaining human mobility and forecasting travel demand. However, the existing literature from psychology does not strictly control potential endogeneity due to ignorance of detailed level-of-service (LOS) variables of alternatives and rational preference in the analysis. Quantitative transportation studies are insufficient in providing explicit behavior mechanisms. This paper aims to fill the gaps by empirically examining the effects of irrational psychological inertia in mode shift behavior with controlling potential endogeneity. A specific-designed comparison experiment is conducted to demonstrate the existence of psychological inertia in mode shift behavior. The effects of dominance in LOS variables and rational preference towards a certain transport mode are controlled to eliminate potential endogeneity in the analysis. The results demonstrate that after controlling the above-mentioned endogeneity, both car and metro users show significantly and substantially larger predilections to previously used transport mode in mode shift scenarios without overturning travel contexts than those in new context mode choice scenarios with noticeable changes in travel contexts. The results support that psychological inertia plays a significant role in mode shift behavior after controlling potential endogeneity. Moreover, this study utilizes hybrid choice modeling to quantitatively measure the effect of psychological inertia. The relationships between travelers’ characteristics and strength of psychological inertia are analyzed as well to shed light on heterogeneity in the strength of psychological inertia. The findings provide solid evidence of psychological inertia in mode shift behavior by a novel method and provide an approach to measure the quantitative effects of psychological inertia along with empirical studies.
|
|
| 8. |
- Haustein, Sonja, et al.
(författare)
-
Risky and anxious-aggressive drivers : A key barrier to traffic safety legislation in Germany
- 2022
-
Ingår i: Transportation Research Part F. - : Elsevier. - 1369-8478 .- 1873-5517. ; 89, s. 84-96
-
Tidskriftsartikel (refereegranskat)abstract
- Traffic safety is high on the agenda of European governments. Yet, countries including Germany maintain policies that are commonly identified as increasing traffic risks, such as speed limits set too high or trends of greater car motorization and mass. To better understand some of the interrelationships of driver characteristics and car segments, this paper identifies different groups of drivers, based on a representative sample of German automobilists (n = 1211). Psychological instruments used to identify driver segments include the Driver Behavior Questionnaire (DBQ), the Multidimensional Driving Style Inventory (MDSI), and the HEXACO Personality Inventory. Based on k-means clustering, we identified four distinct groups: Risky drivers, Showy anxious aggressive drivers, Anxious drivers and Calm drivers. Questions focused on sociodemographics, political orientation, and traffic laws are used to describe these psychographic segments. Findings suggest that Risky and Showy anxious-aggressive drivers represent a greater threat to traffic safety than other driver segments for different reasons: they drive more powerful and larger cars, deliberately violate traffic laws - creating unsafe traffic conditions for others -, and oppose legislation making traffic safer, while also voting for parties holding on to the status quo. As their political choices appear dominated by automobile interests, there are widespread implications for society.
|
|
| 9. |
- Itkonen, Teemu, 1985, et al.
(författare)
-
Characterisation of Motorway Driving Style Using Naturalistic Driving Data
- 2020
-
Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour. - : Elsevier BV. - 1369-8478. ; 69, s. 72-79
-
Tidskriftsartikel (refereegranskat)abstract
- The study of measurable differences between drivers has ramifications for several subfields in traffic and transportation research. Better understanding of the variability in individual driving styles would be especially useful for understanding driver preferences, psychological mechanisms for vehicle control and for developing more realistic traffic simulations. In our study based on a large naturalistic data set, we investigated the driving style of 76 individuals driving in a motorway setting. We discovered that the majority of between-driver variation in keeping longitudinal and lateral safety margins, lane changing frequency, acceleration and speed preference, can be reduced to two dimensions, which we interpret as habitualised motives centred around mental effort and expediency.
|
|
| 10. |
- Kircher, Katja, 1973-, et al.
(författare)
-
A comparison of glance coding approaches for driver attention assessment
- 2024
-
Ingår i: Transportation Research Part F. - : Elsevier. - 1369-8478 .- 1873-5517. ; 100, s. 243-253
-
Tidskriftsartikel (refereegranskat)abstract
- Eye tracking is a common tool to assess drivers’ attentional state, either in real-time with the goal to prevent incidents, or offline, to understand underlying processes. While seemingly objective, eye tracking data can be coded and interpreted in different ways, which can have substantial effects on the results. The objective of this paper is to highlight and discuss the possibilities and limitations of three different approaches to code glance data: the direction-based encoding, the target-based approach, and the purpose-based approach. The direction-based coding scheme describes glances relative to the direction of travel. The target-based approach classifies the glance targets into different categories. The purpose-based approach needs additional layers of information to deduce the reason for the glance. This information encompasses road layout, traffic rules, and the presence and relevance of other traffic.Data from a field study with 23 participants driving an instrumented vehicle on an urban route was used to illustrate differences between the three methods. The results showed that the coding approach clearly affected the interpretation of the measured glance data. A purely target-based approach is limited by its inability to account for spare visual capacity and that also the absence of a target constitutes valuable information, and a purely direction-based approach does not account for the need to scan areas located off forward. The purpose-based approach requires contextual information that can be cumbersome to integrate. Regardless of the approach used, additional layers of contextual information increase understanding and interpretability, potentially at the cost of increased complexity. The three approaches are suitable for different contexts and their feasibility also depends on the availability of additional data. A key message is that context awareness improves the accuracy of driver attention monitoring and inattention identification.
|
|
