Hierarchical Graphs as Organisational Principle and Spatial Model Applied to Pedestrian Indoor Navigation

In this thesis, hierarchical graphs are investigated from two different angles – as a general modelling principle for (geo)spatial networks and as a practical means to enhance navigation in buildings. The topics addressed are of interest from a multi-disciplinary point of view, ranging from Computer Science in general over Artificial Intelligence and Computational Geometry in particular to other fields such as Geographic Information Science. Some hierarchical graph models have been previously proposed by the research community, e.g. to cope with the massive size of road networks, or as a conceptual model for human wayfinding. However, there has not yet been a comprehensive, systematic approach for modelling spatial networks with hierarchical graphs. One particular problem is the gap between conceptual models and models which can be readily used in practice. Geospatial data is commonly modelled - if at all - only as a flat graph. Therefore, from a practical point of view, it is important to address the automatic construction of a graph hierarchy based on the predominant data models. The work presented deals with this problem: an automated method for construction is introduced and explained. A particular contribution of my thesis is the proposition to use hierarchical graphs as the basis for an extensible, flexible architecture for modelling various (geo)spatial networks. The proposed approach complements classical graph models very well in the sense that their expressiveness is extended: various graphs originating from different sources can be integrated into a comprehensive, multi-level model. This more sophisticated kind of architecture allows for extending navigation services beyond the borders of one single spatial network to a collection of heterogeneous networks, thus establishing a meta-navigation service. Another point of discussion is the impact of the hierarchy and distribution on graph algorithms. They have to be adapted to properly operate on multi-level hierarchies. By investigating indoor navigation problems in particular, the guiding principles are demonstrated for modelling networks at multiple levels of detail. Complex environments like large public buildings are ideally suited to demonstrate the versatile use of hierarchical graphs and thus to highlight the benefits of the hierarchical approach. Starting from a collection of floor plans, I have developed a systematic method for constructing a multi-level graph hierarchy. The nature of indoor environments, especially their inherent diversity, poses an additional challenge: among others, one must deal with complex, irregular, and/or three-dimensional features. The proposed method is also motivated by practical considerations, such as not only finding shortest/fastest paths across rooms and floors, but also by providing descriptions for these paths which are easily understood by people. Beyond this, two novel aspects of using a hierarchy are discussed: one as an informed heuristic exploiting the specific characteristics of indoor environments in order to enhance classical, general-purpose graph search techniques. At the same time, as a convenient by- product of this method, clusters such as sections and wings can be detected. The other reason is to better deal with irregular, complex-shaped regions in a way that instructions can also be provided for these spaces. Previous approaches have not considered this problem. In summary, the main results of this work are: • hierarchical graphs are introduced as a general spatial data infrastructure. In particular, this architecture allows us to integrate different spatial networks originating from different sources. A small but useful set of operations is proposed for integrating these networks. In order to work in a hierarchical model, classical graph algorithms are generalised. This finding also has implications on the possible integration of separate navigation services and systems; • a novel set of core data structures and algorithms have been devised for modelling indoor environments. They cater to the unique characteristics of these environments and can be specifically used to provide enhanced navigation in buildings. Tested on models of several real buildings from our university, some preliminary but promising results were gained from a prototypical implementation and its application on the models

Proceedings of the 3rd International Conference on Models and Technologies for Intelligent Transportation Systems 2013

Challenges arising from an increasing traffic demand, limited resource availability and growing quality expectations of the customers can only be met successfully, if each transport mode is regarded as an intelligent transportation system itself, but also as part of one intelligent transportation system with “intelligent” intramodal and intermodal interfaces. This topic is well reflected in the Third International Conference on “Models and Technologies for Intelligent Transportation Systems” which took place in Dresden 2013 (previous editions: Rome 2009, Leuven 2011). With its variety of traffic management problems that can be solved using similar methods and technologies, but with application specific models, objective functions and constraints the conference stands for an intensive exchange between theory and practice and the presentation of case studies for all transport modes and gives a discussion forum for control engineers, computer scientists, mathematicians and other researchers and practitioners. The present book comprises fifty short papers accepted for presentation at the Third Edition of the conference. All submissions have undergone intensive reviews by the organisers of the special sessions, the members of the scientific and technical advisory committees and further external experts in the field. Like the conference itself the proceedings are structured in twelve streams: the more model-oriented streams of Road-Bound Public Transport Management, Modelling and Control of Urban Traffic Flow, Railway Traffic Management in four different sessions, Air Traffic Management, Water Traffic and Traffic and Transit Assignment, as well as the technology-oriented streams of Floating Car Data, Localisation Technologies for Intelligent Transportation Systems and Image Processing in Transportation. With this broad range of topics this book will be of interest to a number of groups: ITS experts in research and industry, students of transport and control engineering, operations research and computer science. The case studies will also be of interest for transport operators and members of traffic administration

Tenth Workshop and Tutorial on Practical Use of Coloured Petri Nets and the CPN Tools Aarhus, Denmark, October 19-21, 2009

This booklet contains the proceedings of the Tenth Workshop on Practical Use of Coloured Petri Nets and the CPN Tools, October 19-21, 2009. The workshop is organised by the CPN group at the Department of Computer Science, University of Aarhus, Denmark. The papers are also available in electronic form via the web pages: http://www.cs.au.dk/CPnets/events/workshop0

African Water Laws: Plural Legislative Frameworks For Rural Water Management in Africa: an international workshop, Johannesburg, South Africa, 26-28 January 2005

Water law / Water management / Water policy / Poverty / River basins / Irrigation systems / Institutions / Wetlands

Computational Theory of Mind for Human-Agent Coordination

In everyday life, people often depend on their theory of mind, i.e., their ability to reason about unobservable mental content of others to understand, explain, and predict their behaviour. Many agent-based models have been designed to develop computational theory of mind and analyze its effectiveness in various tasks and settings. However, most existing models are not generic (e.g., only applied in a given setting), not feasible (e.g., require too much information to be processed), or not human-inspired (e.g., do not capture the behavioral heuristics of humans). This hinders their applicability in many settings. Accordingly, we propose a new computational theory of mind, which captures the human decision heuristics of reasoning by abstracting individual beliefs about others. We specifically study computational affinity and show how it can be used in tandem with theory of mind reasoning when designing agent models for human-agent negotiation. We perform two-agent simulations to analyze the role of affinity in getting to agreements when there is a bound on the time to be spent for negotiating. Our results suggest that modeling affinity can ease the negotiation process by decreasing the number of rounds needed for an agreement as well as yield a higher benefit for agents with theory of mind reasoning.</p

CItyMaker

Due to its complexity, the evolution of cities is something that is difficult to predict and planning new developments for cities is therefore a difficult task. This complexity can be identified on two levels: on a micro level, it emerges from the multiple relations between the many components and actors in cities, whereas on a macro level it stems from the geographical, social and economic relations between cities. However, many of these relations can be measured. The design of plans for cities can only be improved if designers are able to address measurements of some of the relationships between the components of cities during the design process. These measurements are called urban indicators. By calculating such measurements, designers can grasp the meaning of the changes being proposed, not just as simple alternative layouts, but also in terms of the changes in indicators adding a qualitative perception. This thesis presents a method and a set of tools to generate alternative solutions for an urban context. The method proposes the use of a combined set of design patterns encoding typical design moves used by urban designers. The combination of patterns generates different layouts which can be adjusted by manipulating several parameters in relation to updated urban indicators. The patterns were developed from observation of typical urban design procedures, first encoded as discursive grammars and later translated into parametric design patterns. The CItyMaker method and tools allows the designer to compose a design solution from a set of programmatic premises and fine-tune it by pulling parameters whilst checking the changes in urban indicators. These tools improve the designer’s awareness of the consequences of their design moves

CItyMaker:

Due to its complexity, the evolution of cities is something that is difficult to predict and planning new developments for cities is therefore a difficult task. This complexity can be identified on two levels: on a micro level, it emerges from the multiple relations between the many components and actors in cities, whereas on a macro level it stems from the geographical, social and economic relations between cities. However, many of these relations can be measured. The design of plans for cities can only be improved if designers are able to address measurements of some of the relationships between the components of cities during the design process. These measurements are called urban indicators. By calculating such measurements, designers can grasp the meaning of the changes being proposed, not just as simple alternative layouts, but also in terms of the changes in indicators adding a qualitative perception. This thesis presents a method and a set of tools to generate alternative solutions for an urban context. The method proposes the use of a combined set of design patterns encoding typical design moves used by urban designers. The combination of patterns generates different layouts which can be adjusted by manipulating several parameters in relation to updated urban indicators. The patterns were developed from observation of typical urban design procedures, first encoded as discursive grammars and later translated into parametric design patterns. The CItyMaker method and tools allows the designer to compose a design solution from a set of programmatic premises and fine-tune it by pulling parameters whilst checking the changes in urban indicators. These tools improve the designer’s awareness of the consequences of their design moves

Living in a car-free housing development. Motivations and mobility practices of residents in nine developments in Switzerland and Germany

Cars and the system of infrastructures and urban forms built to support them have many negative impacts such as pollution, greenhouse gas emissions and a high land use, particularly in cities. In response to this, car- free housing developments have emerged in different Western European cities. In these real-world laboratories of a mobility transition, residents commit to living without a private car in the long term. To overcome a car- centred society, it is important to understand why some households choose to voluntarily live car-free and move to these developments, and how they are mobile. This thesis represents the first large-scale study of car-free housing residents. It analysed nine developments, five in Switzerland (Burgunder in Bern, FAB-A in Biel/Bienne, Giesserei in Winterthur, Oberfeld in Oster- mundigen and Sihlbogen in Zurich) and four in Germany (Klein Borstel and Saarlandstraße in Hamburg, Stellwerk60 in Cologne and Weißenburg in Münster). These sites include a diversity of car-free developments in terms of different dwelling types (even though six of them represent forms of collaborative housing), sizes, ages and localisations. A mixed methods approach was adopted to study the residents’ profiles, motivations and practices as well as their evaluation of the spatial and social context necessary to live car-free. A self- administered questionnaire survey (n=500) carried out in all nine developments was combined with in-depth interviews (n=50) conducted in six of them. The analyses show that the residents have very particular profiles. They have a high level of education and ethical or altruistic values are very important to them. Nearly half of the households are families. Almost all of them live deliberately without a private car and this does not represent a sacrifice for them. Their motiva- tions for living car-free refer mainly to a combination of practical and personal reasons. The first type of moti- vation includes no need for a car and the availability of alternative transport modes, the second mainly revolves around ecological motivations. Conversely, the affordability of a car as well as health or age reasons are of very little importance. The motivations to move to a car-free housing development are similar, practical reasons such as the accessibility of the location are highlighted, but social aspects such as living in a community are important, too, particularly in the cooperative housing projects. The analyses of the residents’ mobility capital and practices revealed four types of strategies how to be mobile without owning a private car. First, car-free housing residents rely on (augmented) alternative transport modes, i.e. the bicycle (with a trailer or as an e- or a cargo bike), public transport and walking. Second, they use mobility and transport services, including taxis and delivery services, but also limited use of (carsharing or other borrowed) cars. Furthermore, digitalisation facilitates car-free living, especially smartphone apps al- lowing access to all mobility forms and supporting their use. Third, the inhabitants favour car-less accessibility and, thus, proximity often influences the localisation of their everyday activities. Fourth, the community of car-free residents appeared important, too. On a practical level, neighbourly help or common activities in the development facilitate car-free living, but, beyond that, the community also empowers the residents and “nor- malises” this way of life. Despite clear general tendencies for motivations and practices, an important diversity of car-free residents exists. A typology of lifestyles allowed us to uncover them. Based on their values and motivations to live car- free as well as on their mobility practices, six lifestyles of car-free residents were found: ecological, pragmatic and utilitarian cyclists and the same three types of multimodals, ecological, pragmatic and utilitarian. Finally, a certain spatial and social context is also necessary to live car-free. On the one hand, it consists of transport and other infrastructures such as local supply or spaces for common activities in the development. On the other hand, it includes immaterial aspects, particularly social norms allowing to consider car-freeness. In brief, a system of car-free mobility needs to be set up to overcome automobility. It consists of various indi- vidual strategies, but also of a spatial and social context allowing car-free living. -- Les voitures et le système d’infrastructures urbaines construit autour d’elles ont de nombreux impacts négatifs tels que la pollution, les émissions de gaz à effet de serre et une importante consommation d’espace, en parti- culier dans les villes. En réponse à cette problématique, des habitats sans voitures ont émergé dans différentes villes d’Europe occidentale. Dans ces laboratoires d’une transition vers une mobilité durable, les habitant·e·s s’engagent à vivre sans voiture sur le long terme. Pour surmonter une société basée sur la voiture, il est impor- tant de comprendre pourquoi certains ménages choisissent volontairement de vivre sans voiture et d’emména- ger dans ces habitats, ainsi que les caractéristiques de leur mobilité. Cette thèse représente la première étude à grande échelle de résident·e·s d’habitats sans voitures. Elle a ana- lysé neuf quartiers, cinq en Suisse (Burgunder à Berne, FAB-A à Bienne, Giesserei à Winterthour, Oberfeld à Ostermundigen et Sihlbogen à Zurich) et quatre en Allemagne (Klein Borstel et Saarlandstraße à Hambourg, Stellwerk60 à Cologne et Weißenburg à Münster). Ils couvrent la diversité des habitats sans voitures en termes de types de logements (six d’entre eux représentent des formes d’habitat collaboratif), de taille, d’âge et d’emplacements. Une approche basée sur des méthodes mixtes a été adoptée afin d’étudier le profil des ménages, leurs motivations, leurs pratiques, ainsi que leur évaluation du contexte spatial et social nécessaire pour vivre sans voiture. Une enquête par questionnaire auto-administré (n=500) réalisée dans les neuf quartiers considérés a été combinée avec des entretiens approfondis (n=50) menés dans six d’entre eux. Les résultats des analyses démontrent que les habitant·e·s ont des profils particuliers à plusieurs égards. Ils et elles ont souvent un haut niveau de formation et accordent une grande importance à des valeurs éthiques ou altruistes. Presque la moitié des ménages sont des familles. Quasiment tous les ménages vivent volontai- rement sans voiture sans que cela ne représente un sacrifice pour eux. Leurs motivations à vivre sans voiture se réfèrent surtout à une combinaison de raisons pratiques et personnelles. Le premier type de motivations inclut le fait de ne pas avoir besoin d’une voiture ainsi que la disponibilité de modes de transports alternatifs tandis que le deuxième type représente principalement des motivations écologiques. Au contraire, les raisons financières ainsi que de santé ou d’âge n’ont qu’une très faible importance. Les motivations pour emménager dans un habitat sans voitures sont similaires. Les raisons pratiques telles que l’accessibilité de la localisation, mais aussi des aspects sociaux tel que le fait de vivre en communauté, en particulier dans les coopératives, sont mis en évidence. L’analyse du capital de mobilité et des pratiques des résident·e·s a révélé quatre types de stratégies permettant d’être mobile sans posséder une voiture. Premièrement, les habitant·e·s s’appuient sur des moyens de trans- ports alternatifs (améliorés), en particulier le vélo (avec remorque, en tant que vélo-cargo ou avec assistance électrique), les transports publics et la marche. Deuxièmement, ils et elles recourent à des services de mobilité, comme des taxis et des services de livraisons, mais aussi à l’utilisation ponctuelle d’une voiture partagée. De plus, la numérisation facilite la vie sans voitures, particulièrement les applications pour smartphones qui per- mettent l’accès à de nombreuses formes de mobilité et facilitent leur usage. Troisièmement, les habitant·e·s favorisent l’accessibilité sans voiture, et donc souvent la proximité pour leurs activités quotidiennes. Quatriè- mement, la communauté d’habitant·e·s apparait également comme un facteur important. Au niveau pratique, l’aide de voisinage et les activités communes dans l’habitat facilitent le fait de vivre sans voiture. De plus, l’esprit de communauté encourage aussi les habitant·e·s et « normalise » cette manière de vivre. Malgré des tendances générales clairement définies concernant les motivations et les pratiques, une diversité d’habitant·e·s existe. Une typologie des modes de vie permet de les mettre en lumière. Sur la base des valeurs et des motivations des habitant·e·s à vivre sans voiture ainsi que de leurs pratiques de mobilité, six modes de vie ressortent de l’analyse : les cyclistes écologiques, pragmatiques ou utilitaristes ainsi que les mêmes trois types de multimodaux, écologiques, pragmatiques et utilitaristes. Enfin, un contexte spatial et social spécifique est également nécessaire pour vivre sans voiture. Il consiste d’une part en des infrastructures liées à la fois aux transports mais aussi à l’approvisionnement local ou aux activités communes dans l’habitat. D’autre part, le contexte inclut des aspects immatériels, en particulier des normes sociales qui permettent d’envisager une vie sans voiture. En résumé, un système de mobilité sans voiture doit être mis en place pour surmonter l’automobilité. Il consiste à la fois en des stratégies individuelles variées et en un contexte spatial et social permettant de vivre sans voiture. -- Autos und das für sie aufgebaute System an Infrastrukturen haben viele negative Auswirkungen, wie Schad- stoff- und Treibhausgasemissionen und einen hohen Bodenverbrauch, insbesondere in Städten. Als Antwort darauf sind in verschiedenen westeuropäischen Städten autofreie Wohnsiedlungen entstanden. In diesen Re- allaboren einer Mobilitäts-Transformation verpflichten sich die Bewohner*innen dazu, langfristig ohne eige- nes Auto zu leben. Um eine autodominierte Gesellschaft zu überwinden ist es wichtig zu verstehen, weshalb Haushalte sich freiwillig dazu entscheiden autofrei zu leben und in diese Siedlungen zu ziehen, und wie sie mobil sind. Diese Doktorarbeit beinhaltet die erste gross angelegte Studie von Bewohner*innen autofreier Siedlungen. Sie hat neun davon analysiert, fünf in der Schweiz (Burgunder in Bern, FAB-A in Biel, Giesserei in Winterthur, Oberfeld in Ostermundigen und Sihlbogen in Zürich) und vier in Deutschland (Klein Borstel und Saarland- straße in Hamburg, Stellwerk60 in Köln und Weißenburg in Münster). Diese beinhalten die unterschiedlichen Arten von autofreien Wohnsiedlungen bezüglich Wohnform (auch wenn sechs davon Genossenschaften oder Wohnprojekte sind), Grösse, Alter und Lage. Ein Mixed-Methods-Ansatz wurde angewandt um die Profile, Motivationen und Praktiken der Bewohner*innen zu erforschen, sowie deren Einschätzung des notwendigen räumlichen und sozialen Kontexts um autofrei zu leben. Eine Befragung mit einem selbst auszufüllenden Fra- gebogen (n=500) in allen neuen Siedlungen wurde kombiniert mit ausführlichen Interviews (n=50), die in sechs Siedlungen geführt wurden. Die Resultate zeigen, dass die Bewohner*innen sich durch sehr spezifische Profile auszeichnen. Sie verfügen über ein hohes Ausbildungsniveau und ethische oder altruistische Werte sind ihnen am wichtigsten. Beinahe die Hälfte der Haushalte sind Familien. Fast alle von ihnen leben freiwillig ohne eigenes Auto und dies bedeu- tet kein Verzicht für sie. Ihre Motivationen autofrei zu leben beziehen sich hauptsächlich auf eine Kombination aus praktischen und persönlichen Gründen. Erstere beinhalten keinen Bedarf für ein Auto und die Verfügbar- keit von alternativen Transportmitteln, letztere vorwiegend ökologische Motivationen. Finanzielle sowie Ge- sundheits- und Altersgründe spielen hingegen nur für sehr wenige Haushalte eine Rolle. Die Motivationen, in eine autofreie Wohnsiedlung zu ziehen, sind ähnlich. Praktische Gründe wie die Erreichbarkeit der Lage der Siedlung werden hervorgehoben, aber auch soziale Aspekte wie das Gemeinschaftsleben, insbesondere in den Genossenschaften. Die Analysen des Mobilitätskapitals und der Mobilitätspraktiken der Bewohner*innen zeigen vier Arten von Strategien, die ihnen ermöglichen, ohne eigenes Auto mobil zu sein. Erstens bauen die Bewohner*innen auf die Nutzung von (erweiterten) alternativen Transportformen, d.h. das Velo (mit Anhänger oder in Form eines E- oder Cargo-Bikes), öffentliche Verkehrsmittel und zu Fuss gehen. Zweitens nutzen sie Mobilitätsdienstleis- tungen wie Taxis und Lieferdienste, aber auch punktuell Carsharing- oder andere Leih-Autos. Ausserdem ver- einfacht die Digitalisierung autofrei leben, insbesondere Smartphone-Apps, welche Zugang zu allen Mobili- tätsformen ermöglichen und deren Nutzung unterstützen. Drittens favorisieren die Bewohner*innen autofreie Erreichbarkeit und daher für ihre Alltagsaktivitäten oft Ziele in der Nähe. Viertens erschien die Gemeinschaft der Bewohner*innen auch als wichtig. Auf der praktischen Ebene erleichtern Nachbarschaftshilfe oder Ge- meinschaftsaktivitäten in der Siedlung autofreies Leben, darüber hinaus stärkt die Gemeinschaft die Bewoh- ner*innen auch und „normalisiert“ diese Lebensform. Obschon für Motivationen und Praktiken klare Tendenzen bestehen, existiert eine grosse Vielfalt an Bewoh- ner*innen. Eine Lebensstil-Typologie ermöglicht es, diese hervorzuheben. Basierend auf den Wertvorstellun- gen und Motivationen der Bewohner*innen, autofrei zu leben, wie auch auf deren Mobilitätspraktiken, wurden sechs Lebensstile gefunden: ökologische, pragmatische und nutzenorientierte Velofahrende sowie die selben drei Typen von Multimodalen, ökologische, pragmatische und nutzenorientierte. Schliesslich braucht es auch einen räumlichen und sozialen Kontext, um autofrei zu leben. Einerseits besteht dieser aus Verkehrs- und anderen Infrastrukturen wie Nahversorgung oder Räumen für Gemeinschaftsakti- vitäten in der Siedlung. Andererseits beinhaltet dieser aber auch immaterielle Aspekte, insbesondere soziale Normen welche ermöglichen, Autofreiheit in Betracht zu ziehen. Zusammengefasst muss ein System von autofreier Mobilität aufgebaut werden, um die Automobilität zu über- winden. Es besteht aus vielfältigen individuellen Strategien, aber auch aus einem räumlichen und sozialen Kontext, der autofreies Leben ermöglicht

Simulated cognitive topologies: automatically generating highly contextual maps for complex journeys

As people traverse complex journeys, they engage in a number of information interactions across spatial scales and levels of abstraction. Journey complexity is characterised by factors including the number of actions required, and by variation in the contextual basis of reasoning such as a transition between different modes of transport. The high-level task of an A to B journey decomposes into a sequence of lower-level navigational sub-tasks, with the representation of geographic entities that support navigation during, between and across sub-tasks, varying relative to the nature of the task and the character of the geography. For example, transitioning from or to a particular mode of transport has a direct bearing on the natural level of representational abstraction that supports the task, as well as on the overall extent of the task’s region of influence on the traveller’s focus. Modern mobile technologies send data to a device that can in theory be context-specific in terms of explicitly reflecting a traveller’s heterogeneous information requirements, however the extent to which context is explicitly reflected in the selection and display of navigational information remains limited in practice, with a rigid, predetermined scale-based hierarchy of cartographic views remaining the underlying representational paradigm. The core subject of the research is the context-dependent selection and display of navigational information, and while there are many and varied considerations in developing techniques to address selection and display, the central challenge can simply be articulated as how to determine the probability, given the traveller’s current context, that a feature should be in the current map view. Clearly this central challenge extends to all features in the spatial extent, and so from a practical perspective, research questions centre around the initial selection of a subset of features, and around determining an overall probability distribution over the subset given the significance of features within the hierarchically ordered sequence of tasks. In this thesis research is presented around the use of graph structures as a practical basis for modeling urban geography to support heterogenous selections across viewing scales, and ultimately for displaying highly context-specific cartographic views. Through an iterative, empirical research methodology, a formalised approach based on routing networks is presented, which serves as the basis for modeling, selection and display. Findings are presented from a series of 7 situated navigation studies that included research with an existing navigation application as well as experimental research stimuli. Hypotheses were validated and refined over the course of the studies, with a focus on journey-specific regions that form around the navigable network. Empirical data includes sketch maps, textual descriptions, video and device interactions over the course of complex navigation exercises. Study findings support the proposed graph architecture, including subgraph classes that approximate cognitive structures central to natural comprehension and reasoning. Empirical findings lead to the central argument of a model based on causal mechanisms, in which relations are formalised between task, selection and abstraction. A causal framework for automatically determining map content for a given journey context is presented, with the approach involving a conceptual shift from treating geographic features as spatially indexed records, to treating them as variables with a finite number of possible states. Causal nets serve as the practical basis of reasoning, with geographic features being represented by variables in these causal structures. The central challenge of finding the probability that a variable in a causal net is in a particular state is addressed through a causal model in which journey context serves as the evidence that propagates over the net. In this way, complex heterogeneous selections for interactive multi-scale information spaces are expressed as probability distributions determined through message propagation. The thesis concludes with a discussion around the implications of the approach for the presentation of navigational information, and it is shown how the framework can support context-specific selection and disambiguation of map content, demonstrated through the central use case of navigating complex urban journeys