A two-stage incentive mechanism for rebalancing free-floating bike sharing systems: Considering user preference

Free-floating bike sharing (FFBS) provides citizens with a flexible way for traveling. The operational performance of such systems is impacted by the imbalance problem of demand and supply. This paper proposes the first two-stage incentive mechanism to improve the service quality of FFBS. While inspired by the user-based rebalancing approach in station-based bike sharing (SBBS), our work is different from existing studies because location optimization is a new problem in FFBS and user preference is considered for the first time. We propose three mechanisms that are pick-up incentives, drop-off incentives, and two-stage incentives. When modeling users’ behavioral responses to incentive mechanisms, we think users prefer drop-off incentives to pick-up incentives, which is supported by a survey study. Each incentive offer is composed of a location and a price. To decide the suggested origin or destination, we first figure out the supply and demand of all valid locations based on Radiant Service Theory (RST) and then search the most problematic location comparing current inventory and future demand. The pricing scheme is modified Budgeted Procurement using Upper Confidence Bounds (BP-UCB). Simulation experiments validate the effectiveness of incentive mechanisms based on historical data from Capital BikeShare program. Results show that the service level of bike sharing systems can be significantly improved by three incentive mechanisms. The two-stage incentive mechanism unexpectedly shows no advantage over pick-up incentives. Sensitivity analysis further indicates that user preference will influence the ranking of two single-stage incentive mechanisms.     

A two-part evaluation approach for measuring the usability and user experience of an Augmented Reality-based assistance system to support the temporal coordination of spatially dispersed teams

One key predictor of team performance and productivity is the teams’ ability to coordinate its subtasks as precisely as possible over time. Thereby, the quality of the temporal coordination in teams is highly dependent on several cognitive team skills, like for instance the ability to build a precise and stable mental model of the situation (shared situation awareness) and of the team task process (task state awareness/ TSA). To support these cognitive skills in teams, various methods and trainings already exist. However, considering teams that work de-located, the prerequisites and therefore the requirements for team supportive methods change. This work presents the results of an empirical usability and user experience (UX) study of an interface for an Augmented Reality-based assistance system for spatially dispersed teams, called Ambient Awareness Tool (AAT). The AAT interface consists of graphical information about the teamwork process and aims at enhancing the TSA of the team, thereby supporting its temporal coordination. Within the framework of a participatory design process we conducted a two-part expert-user-study, comprising a laboratory experiment for the evaluation of the interface usability and a follow-up online survey to additionally investigate the UX. By means of the usability scores we first inferred three interface configuration clusters. A subsequent UX evaluation then allowed us to designate the configuration cluster with the highest usability and UX scores. As a result, we defined one interface configuration that will be investigated concerning its actual impact on the temporal coordination of spatially dispersed teams in a further study.     

The influence of system transparency on trust: Evaluating interfaces in a highly automated vehicle

Previous studies indicate that, if an automated vehicle communicates its system status and intended behaviour, it could increase user trust and acceptance. However, it is still unclear what types of interfaces will better portray this type of information. The present study evaluated different configurations of screens comparing how they communicated the possible hazards in the environment (e.g. vulnerable road users), and vehicle behaviours (e.g. intended trajectory). These interfaces were presented in a fully automated vehicle tested by 25 participants in an indoor arena. Surveys and interviews measured trust, usability and experience after users were driven by an automated low-speed pod. Participants experienced four types of interfaces, from a simple journey tracker to a windscreen-wide augmented reality (AR) interface which overlays hazards highlighted in the environment and the trajectory of the vehicle. A combination of the survey and interview data showed a clear preference for the AR windscreen and an animated representation of the environment. The trust in the vehicle featuring these interfaces was significantly higher than pretrial measurements. However, some users questioned if they want to see this information all the time. One additional result was that some users felt motion sick when presented with the more engaging content. This paper provides recommendations for the design of interfaces with the potential to improve trust and user experience within highly automated vehicles.     

Rôle de l’émotion dans l’acceptabilité d’un produit : évaluation des composantes cognitive,motivationnelle et subjective

To anticipate a product commercial success, companies aim to ensure that product's characteristics are involving users and triggering a positive first user experience as well as all along product's life span. Among these characteristics, triggering users’ emotions is particularly relevant. This article aims to present the different approaches integrating the emotion generated by products. In order to illustrate the emotional potential of certain products a selection of 14 photographs of products was evaluated by 87 participants. Results reveal a significant correlation between cognitive, motivational and subjective components of emotions. A reflexion about the integration of cognitive appraisal assessment and motivational action readiness evaluation into a wilder emotional model is provided. Thus, emotions triggered by a product appear to be a stake for designers and an important variable to introduce in acceptability or user experience models.     

User-related assessment of a Driver Assistance System for Continuous Support – A field trial

A Driver Assistance System for Continuous Support continuously evaluates the status of the host vehicle as well as the surrounding traffic based on information from on-board sensors. When the system detects a hazard, it issues a warning to the driver, depending on the degree of the hazard. The effects of this system on driver behaviour and acceptance were evaluated in a field trial carried out in 2013. Twenty-four drivers took part in test drives with a within-subject design along a 53 km test route containing motorway and rural-road sections. Driving data was logged and the test drivers were observed by means of an in-car observation method (Wiener Fahrprobe); in this case by two observers in the car along with the driver. Questionnaires were used to assess the drivers’ comprehension of and reaction to the system. The system was successful in affecting driver behaviour in terms of lower speed when negotiating curves. Positive effects were found in the form of better speed adaptation to the situation during driving with the system activated. Also, lane choice and lane change improved with the system on. When it came to speed limit compliance, driving speed in general and longitudinal and lateral positioning, no effects could be found. No major differences were found regarding distance to the vehicle in front, overtaking manoeuvres, stopping behaviour at intersections, driving against yellow at traffic lights and interaction behaviour with other road users while driving with or without the system. On the negative side, it was noted that only during driving with the system activated did the test drivers make turns at intersections at too high speeds. In addition, more errors associated with dangerous distance to the side were observed with the system activated. In terms of the emotional state of the driver, the only difference found was that the drivers felt an increase in irritation. Regarding subjective workload, the drivers only assessed one item, i.e. whether their performance decreased statistically significantly while driving with the system. The test drivers were of the opinion that the system was useful, and that it would enhance safety especially in overtaking manoeuvres on motorways. The blind-spot warning was found especially useful in the overtaking process. The drivers appreciated the fact that the system did not give information all the time.     

“Leave Your Comment Below”: Can Biased Online Comments Influence Our Own Prejudicial Attitudes and Behaviors?

Increased use of online communication in everyday life presents a growing need to understand how people are influenced by others in such settings. In this study, online comments established social norms that directly influenced readers' expressions of prejudice both consciously and unconsciously. Participants read an online article and were then exposed to antiprejudiced or prejudiced comments allegedly posted by other users. Results revealed that exposure to prejudiced (relative to antiprejudiced) comments influenced respondents to post more prejudiced comments themselves. In addition, these effects generalized to participants' unconscious and conscious attitudes toward the target group once offline. These findings suggest that simple exposure to social information can impact our attitudes and behavior, suggesting potential avenues for social change in online environments.     

Exploring expert perceptions about the cyber security and privacy of Connected and Autonomous Vehicles: A thematic analysis approach

Connected and Autonomous Vehicles (CAVs) constitute an automotive development carrying paradigm-shifting potential that may soon be embedded into a dynamically changing urban mobility landscape. The complex machine-led dynamics of CAVs make them more prone to data exploitation and vulnerable to cyber attacks than any of their predecessors increasing the risks of privacy breaches and cyber security violations for their users. This can adversely affect the public acceptability of CAVs, give them a bad reputation at this embryonic stage of their development, create barriers to their adoption and increased use, and complicate the business models of their future operations. Therefore, it is vital to identify and create an in-depth understanding of the cyber security and privacy issues associated with CAVs, and of the way these can be prioritised and addressed. This work employs 36 semi-structured elite interviews to explore the diverse dimensions of user acceptance through the lens of the well-informed CAV experts that already anticipate problems and look for their solutions. Our international interviewee sample represents academia, industry and policy-making so that all the key stakeholder voices are heard. Thematic analysis was used to identify and contextualise the factors that reflect and affect CAV acceptance in relation to the privacy and cyber security agendas. Six core themes emerged: awareness, user and vendor education, safety, responsibility, legislation, and trust. Each of these themes has diverse and distinctive dimensions and are discussed as sub-themes. We recommend that mitigating the cyber security and privacy risks embedded in CAVs require inter-institutional cooperation, awareness campaigns and trials for trust-building purposes, mandatory educational training for manufacturers and perhaps more importantly for end-users, balanced and fair responsibility-sharing, two-way dynamic communication channels and a clear consensus on what constitutes threats and solutions.     

Effects of visual factors during automated driving of mobility scooters on user comfort: An exploratory simulator study

An automated mobility scooter is expected to provide convenient and safe transportation for users in their living area. However, there is limited research on user comfort compared to that on user safety for the automated driving of mobility scooters. Because the user does not perform driving tasks in automated driving, the visual information from the peripheral environment and visual behavior is expected to closely affect the psychological comfort of the user. This study clarifies the effects of factors related to the automated driving of mobility scooters and the peripheral environment on the visual behavior and psychological comfort of the user. Effects of driving velocity and pedestrian density on the visual behavior and psychophysiological responses of users were investigated via a driving simulator. The results showed that automated driving in an environment with a high pedestrian density can result in a decrease in fixation duration, deactivation of visual processing, sympathetic activation, and feeling of negative emotion. This implies that the assessment of visual behaviors of users is important for the design of automated mobility scooters to improve user comfort.     

Factors that influence the acceptance of future shared automated vehicles – A focus group study with United Kingdom drivers

The development of Shared Automated Vehicles (SAVs) is well underway to provide mobility as a service (MaaS) and bring benefits such as reduced traffic congestion, reduced reliance on privately owned vehicles and increased independence to non-drivers. To realise the benefits of SAVs, adoption by private vehicle users is crucial. Previous research has shown this subset of users as the least likely to adopt SAVs, and it is not well understood what factors are important to achieve such adoption. The purpose of this study is to obtain an in-depth understanding of attitudes, perceptions and preferences that influence the acceptance of future SAVs for drivers. This paper presents the results from an online asynchronous focus group study with 21 British drivers as participants. From the analysis, Service Quality, Trust and Price Value emerged as the three most prominent factors to understand user acceptance of SAVs. These three main factors may be of prime importance for convincing naïve private car owners to accept high-speed SAVs. Productive use of travel time has been frequently mentioned in previous research as a benefit of vehicle automation but was scarcely mentioned by participants in this study. Shared Space Quality in introduced as an indicator for Service Quality, together with Security and Trusting Co-passengers as two indicators of Trust. Based on the findings, this paper concludes with a conceptual SAV technology acceptance model is introduced, with the results added as extended model predictors to the Unified Theory of Acceptance and Use of Technology (UTAUT2).