David Jonietz

Axon Vibe

The IARAI Traffic4cast competitions at NeurIPS 2019 and 2020 showed that neural networks can successfully predict future traffic conditions 1 hour into the future on simply aggregated GPS probe data in time and space bins. We thus reinterpreted the challenge of forecasting traffic conditions as a movie completion task. U-Nets proved to be the winni...

Managing data quality is a central task for Machine Learning (ML) applications but often done in an ad hoc manner. Particular challenges for data quality evaluation include ensuring the validity and reproducibility of its results, especially in the context of versioned, multi-step data processing pipelines and increased reuse of data sets for a ran...

Though GPS-based human trajectory data have been commonly used in travel surveys and human mobility studies, missing data or data gaps that are intrinsically relevant to research reliability remain a critical and challenging issue. This study proposes a novel framework for imputing data gaps based on frequent-pattern mining and time geography, whic...

The IARAI Traffic4cast competition at NeurIPS 2019 showed that neural networks can successfully predict future traffic conditions 15 minutes into the future on simply aggregated GPS probe data in time and space bins, thus interpreting the challenge of forecasting traffic conditions as a movie completion task. U-nets proved to be the winning archite...

Measures of spatial autocorrelation like Moran's I do not take into account information about the reliability of observations. In a context of mobile sensors, however, this is an important aspect to consider. Mobile sensors record data asynchronously and capture different contexts, which leads to considerable heterogeneity. In this paper we propose...

Recently, Generative Adversarial Networks (GANs) have demonstrated great potential for a range of Machine Learning tasks, including synthetic video generation, but have so far not been applied to the domain of modeling geographical processes. In this study, we align these two problems and - motivated by the potential advantages of GANs compared to...

Many of today's urgent challenges, especially climate change and green house gas emissions are closely linked to the movement of people and goods. A possible path towards a more sustainable transport sector is given by the concept of Mobility as a Service (MaaS). SBB Green Class is one of the first large pilot projects for a multi-modal mobility fl...

Nowadays, most people carry around a powerful smartphone which is well suited to constantly monitor the location and sometimes even the activity of its user. This makes tracking prevalent and leads to a large number of projects concerned with trajectory data. One area of particular interest is transport and mobility, where data is important for urb...

Technological advances, infrastructural limits and the demands for more ecologically sustainable transport lead to a rapid change in the ways we perceive and use mobility. A potential pillar for future mobility is Mobility as a Service (MaaS), where multiple modes of transport are integrated and made available as an easily accessible, packaged offe...

Obgleich der Mobilität als integralem Bestandteil unserer modernen Gesellschaft eine besondere Rolle zukommt, stellt sie uns auch vor grosse Herausforderungen, wie etwa kontinuierlich zunehmende CO2 Emissionen oder Verkehrsstaus. Ein grosses Potential diesen zu entgegnen wird häufig der weiten Verbreitung moderner, mit GPS-Empfängern ausgerüstetete...

For next place prediction, machine learning methods which incorporate contextual data are frequently used. However, previous studies often do not allow deriving generalizable methodological recommendations, since they use different datasets, methods for discretizing space, scales of prediction, prediction algorithms, and context data, and therefore...

With the emergence of new mobility options and various initiatives to increase the sustainability of our travel behaviour, it is desirable to gain a deeper understanding of our behavioural reactions to such stimuli. Although it is now possible to use GPS-tracking to record people’s movement behaviour over a longer period, there is still a lack of c...

Nowadays, most people own a smartphone which is well suited to constantly record the movement of its user. One use of the gathered mobility data is to provide users with feedback and suggestions for personal behavior change. Such eco-feedback on mobility patterns may stimulate users to adopt more energy-efficient mobility choices. In this paper, we...

With the emergence of ubiquitous movement tracking technologies, developing systems which continuously monitor or even influence the mobility behaviour of individuals in order to increase its sustainability is now possible. Currently, however, most approaches do not move beyond merely describing the status quo of the observed mobility behaviour, an...

This work in progress paper proposes a novel approach for evaluating the level of motivation of hikers who are guided by a location-based mobile learning application (LBML) through a nature reserve. The aim is to extract this information, which is needed for evaluating the motivating effect of the digital tool, by tracking the hikers’ movements, an...

GoEco! is one of several smartphone applications that perform automatic mobility tracking. In contrast to many others, it uses the tracked movement data to compute possible behavioral improvements of its users, and provides this assessment as eco-feedback in various forms. These include booklets detailing user journeys and possible alternatives in...

Current popular multi-modal routing systems often do not move beyond combining regularly scheduled public transportation with walking, cycling or car driving. Seldom included are other travel options such as carpooling, carsharing, or bikesharing, as well as the possibility to compute personalized results tailored to the specific needs and preferen...

GoEco! is one of several smartphone applications that perform automatic mobility tracking. In contrast to many others, it uses the tracked movement data to compute possible behavioral improvements of its users, and provides this assessment as eco-feedback in various forms. These include booklets detailing user journeys and possible alternatives in...

Though the wayfinding process is inherently uncertain, most models of wayfinding do not offer sufficient possibilities for modeling uncertainty. Such modeling approaches, however, are required to engineer assistance systems that recognize, predict, and react to a wayfinder's uncertainty. This paper introduces a conceptual framework for modeling unc...

During pedestrian navigation in outdoor urban environments we often utilize assistance systems to support decision-making. These systems help wayfinders by providing relevant information withing the context of their surroundings, e.g., landmark-based instructions of the type "turn left at the church". Next to the instruction type and content, also...

Since the late 1990s, GNSS-assisted movement tracking technologies have gradually replaced traditional travel survey approaches, such as face-to-face interviews, mailout/mail-back or telephone surveys. A practical problem, however, is posed by insufficient data quality, especially data incompleteness. In fact, detecting and quantifying recording ga...

Volunteered Geographic Information (VGI) is a growing area of research. This Special Issue aims to capture the main trends in VGI research based on 16 original papers, and distinguishes between two main areas, i.e., those that deal with the characteristics of VGI and those focused on applications of VGI. The topic of quality assessment and assuranc...

Although there are numerous studies in which movement trajectories were analysed based on their geometry alone, a more holistic interpretation requires their contextual setting to be incorporated into the analytical process as well. Among other influences, for instance, several attributes of the underlying physical space can have an effect on movem...

Electric bicycles offer a convenient transport alternative for short to medium distance travels. Due to their small size, low cost, and environment-friendly nature, the number of sold bikes is increasing steadily, not only for private use, but also for company fleets, free-floating mobility systems, and bike-sharing providers. This increment leads...

Users of Location-Based Services (LBS) increasingly expect them to be personalized in the sense of being tailored to their individual needs and preferences. As a prerequisite for successful personalization, the process of user profiling extracts and stores a set of rules, settings, needs, interests, behaviors and preferences which virtually represe...

The project GoEco! takes advantage of the wide availability of smartphones, in order to overcome the traditional awareness-raising approach used to foster sustainable mobility and exploit eco-feedback, social norms and peer pressure elements in an ICT-based motivation system. In particular, it uses a smartphone app to analyze how we can encourage p...

(1) Background: Due to the advent of Volunteered Geographic Information (VGI), large datasets of user-generated Points of Interest (POI) are now available. As with all VGI, however, there is uncertainty concerning data quality and fitness-for-use. Currently, the task of evaluating fitness-for-use of POI is left to the data user, with no guidance fr...

Öffentliche Anlagen, wie Haltestellen oder Plätze, müssen sich aufgrund gesellschaftlicher Veränderungen und daraus resultierenden wandelnden Ansprüchen im Laufe der Zeit Umbaumaßnahmen unterziehen. Bedingt durch die hohen Kosten ist es wünschenswert die Reaktionen der Nutzer dieser Räume bereits in der Planungsphase abschätzen zu können. Hierfür h...

This research is motivated by the discrepancy between the spatial model underlying current geographical information systems (GIS) and the human way of structuring space into meaningful spatial units, which are generally referred to as places. Focusing on their functional dimension with regards to human action, this thesis presents a computational m...

Recently, location-based navigation systems have evolved from purely car-centered services to incorporate route planning for other means of transportation, such as walking or cycling. In this context, a particular challenge lies in the com-putation of optimal routes for pedestrians, who expect a high walkability of their urban environment. In parti...

Pedestrians are highly heterogeneous with regards to their physical capabilities and preferences, which in turn determine their individual infrastructural needs. Other than in current pedestrian navigation systems, therefore, the possibility to compute personalized walking routes would be desirable, a precondition of which, however, is to derive de...

This study is based on the problem of calculating route probability for car trips from an unknown origin to a fixed destination. A method, which represents the uncertainty regarding the location of the origin as a polygon with a large set of potential candidate points, is tested on the exemplary case study of taxi drivers approaching a train statio...

Ecological psychology focuses on the flow of information between an animal and its physical surroundings. J. J. Gibson, one of its most famous advocates, presented the concept of affordances to describe the reciprocity of functional relations between humans and their environment. Until today, his work has provided a theoretical basis for various st...

Negative effects of motorized transportation are often locally concentrated in the vicinity of certain destinations, such as airports, malls or train stations. For transportation planning, modeling the access routes to these locations is particularly challenging, mainly because the origins of the car drivers are unknown. In this study, probable acc...

During the last decades, the epidemiological research has given indications that mental diseases including depressions and anxiety disorder can be related to socio-economic, as well as to environmental risk factors. In this project, geodata is collected and maps showing the potential risk of mental stress in urban environments (urban stress) are cr...

Uncertainty in location information can affect the results of network-based route calculations to a high degree. In this study, a routing scenario is analysed where the destination is known, but the location of the point of origin can only approximately be described as “somewhere inside a polygon”. Using the concrete example of car-driving football...

The concept of place has sparked major research activities in various disciplines, including Geography, Spatial Cognition and, more recently, GIScience. Although it represents a vital characteristic of human conceptualizations of space, however, the full range of place-related aspects has not yet been explored, which generates major difficulties fo...

In their everyday decision processes, humans depend on their ability to evaluate the suitability of environmental objects for specific actions. Suitability can therefore be understood as an abstract quality that is determined by properties of both the human agent and the environment as well as the action to be performed. The notion of such mutual d...

In this paper, a framework for modelling the suitability of urban networks for pedestrians is presented. Based on the psychological theory of affordances, a model of spatial suitability is developed that acknowledges the fact that suitability must always be analysed relative to the agent, the task and the environment. We extend existing affordance...

In zahlreichen umweltpsychologischen Studien konnte unlängst die Relevanz von Landschaft als wichtiger Gesundheitsressource aufgezeigt werden. Das Konzept der therapeutischen Landschaften beschreibt dieses gesundheitsfördernde Potenzial und identifiziert Umweltkriterien, die als Indikatoren hierfür dienen können. Trotz dieser Erkenntnisse und obwoh...

Attempts to evaluate the walkability of an urban transporta- tion network, meaning its suitability for pedestrians, have traditionally taken an environment-centered view, thereby neglecting the walkers per- spective. In order to take into account the fact that walkability is a mental construct, we propose an integrated model of walkability based on...

Empirische Studien konnten unlängst einige räumliche Eigenschaften der bebauten Umwelt identifizieren, welche in statistisch signifikanter Weise Fahrradverkehr stimulieren oder aber hemmen können. Vor allem im englischsprachigen Raum werden diese Faktoren häufig unter dem Begriff der Bikeability, also der Eignung einer bestimmten Umgebung zum Fahrr...

Representing a critical factor for maintaining the economic, cultural and social functionality of city centers, accessibility has traditionally been a central concept in urban transportation planning. However, when modeling urban accessibility, approaches have generally concentrated on motorized means of transportation, neglecting the fact that non...