Designing travel behaviour change interventions: a spatiotemporal perspective

Date
2017-12
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH SUMMARY : Against the background of unprecedented growth in private vehicle ownership and the entrenchment of the private car in everyday life, the past decades have seen a growing and ongoing academic and policy debate on how to encourage individuals to change to more sustainable ways of travelling; for instance, with voluntary travel behaviour change (VTBC) interventions. VTBC interventions aim to alter travel behaviour by providing information. In recent years, a large body of research has focused on the evaluation of the effectiveness of these programmes. However, no consensus has been reached on the question of whether a broad implementation of VTBC programmes is effective in stimulating people to use more sustainable ways of travelling. This dissertation argues that location-aware technologies, particularly GPSenabled smartphones, could potentially augment the research on VTBC interventions. Smartphones can not only source data (such as place and time of travel or activity) but can also provide individuals with real-time information, feedback, and suggestions for alternative behaviour or travel options.. However, between sourcing the data and relaying feedback to individual commuters, significant research is required on how to obtain, clean, and interpret the data, as well as on how to account for individual spatiotemporal accessibility. GPS data need to be collected and analysed systematically; especially in the context of evaluating the effectiveness of VTBC interventions in which effect sizes are known to be small and inconspicuous. As such, the translation of raw GPS trajectories into activity episodes and the best estimation of a travelled route are pivotal. Methods of activity recognition were explored with advanced machine learning algorithms, and two approaches for identifying travelled routes were proposed. Furthermore, it was demonstrated how spatiotemporal measurements could aid the design of VTBC interventions. Attention was drawn to the time-geographical concepts of activity spaces and potential path areas. Based on the examination of GPS tracks with different two-dimensional operationalisations of activity spaces, it was found that the density of opportunities within an activity space is related to the size of the activity space: larger activity spaces have lower densities of opportunities than smaller activity spaces. This may suggest that individuals who have a low opportunity density are less likely to respond to external stimuli and/or awareness programmes than individuals who have a high opportunity density. In turn, potential path areas were used to establish to what extent individuals have different spatiotemporal opportunities that will enable behavioural change in travel and activity. The findings indicate that location-aware technologies hold great potential to supplement transport geographical-research. Moreover, the results show that the incorporation of spatiotemporal measurements is crucial to consider for the design, implementation, and evaluation of VTBC interventions. The added value of seemingly new technologies, such as GPS, is that they can be easily integrated into a larger spatiotemporal framework of analysis. However, one has to be careful not to consider GPS as a panacea, because GPS data and technology also have some drawbacks. Careful consideration should go into application development, sample selection, site selection, and data imputation.
AFRIKAANSE OPSOMMING : Teen die agtergrond van ʼn ongekende groei in privaatvoertuigeienaarskap en die volledige integrering van die private motor in die alledaagse lewe, het die afgelope dekades 'n groeiende en volgehoue akademiese- en beleidsdebat gesien oor hoe om individue aan te moedig om oor te skakel na meer volhoubare maniere van reis, met onder meer intervensies om vrywillige reisgedragverandering (VRGV) te stimuleer. VRGV-intervensies poog om reisgedrag te verander deur inligting aan motorgebruikers te verskaf. 'n Groot deel van die huidige navorsing fokus op die evaluering van die effektiwiteit van hierdie programme. Daar is egter steeds geen konsensus oor of 'n breë implementering van VRGV-programme effektief is om mense te stimuleer om meer volhoubare maniere van reis te gebruik nie. Hierdie proefskrif beweer dat plekbewuste tegnologieë, veral Globale Posisionering Stelsel (GPS)-geaktiveerde slimfone, moontlik die navorsing oor VRGV -intervensies kan ondersteun. Slimfone kan nie net data versamel (soos plek en tyd van reis of aktiwiteite) nie, maar kan ook individue intyds van inligting voorsien en terugvoering en voorstelle gee vir alternatiewe gedrag en vervoeropsies. Tussen die verkryging van die data en die terugvoering van inligting aan pendelaars, word heelwat navorsing benodig oor hoe om die data te verkry, skoon te maak en te interpreteer, asook hoe om rekening te hou met individuele ruimtelike-temporale toeganklikheid. GPS-data moet versamel en sistematies ontleed word, veral in die konteks van die evaluering van die effektiwiteit van VRGV intervensies waarin effekgroottes dikwels klein en onopsigtelik is. As sodanig is die verwerking van rou GPS-trajekte in aktiwiteite-episodes en die beste beraming van roetekeuse noodsaaklik. Metodes van aktiwiteitsherkenning is ondersoek met gevorderde masjienleeralgoritmes en twee benaderings vir die identifisering van gekose roete is voorgestel. Verder is getoon hoe ruimtelike-temporale metings die ontwerp van VRGV-intervensies kan help. Aandag is gevestig op die tyd-geografiese konsepte van aktiwiteitsruimtes en potensiële roete areas. Op grond van die ondersoek van GPS-data met verskillende twee-dimensionele operasionele aktiwiteitsareas, is bevind dat die digtheid van geleenthede binne 'n aktiwiteitsruimte verband hou met die grootte van die aktiwiteitsruimte: groter aktiwiteitsruimtes het laer digtheid van geleenthede as kleiner aktiwiteitsruimtes. Dit kan impliseer dat individue wat 'n lae geleentheidsdigtheid ervaar in hulle aktiwiteitsruimte, minder geneig sal wees om op eksterne stimuli en/of bewusmakingsprogramme te reageer as individue wat 'n hoë geleentheidsdigtheid het. Op hul beurt is potensiële roete areas gebruik om vas te stel tot watter mate individue oor verskillende ruimtelike-temporale geleenthede beskik wat gedragsverander (vervoer en aktiwiteite) moontlik maak. Die bevindings dui daarop dat plekbewuste tegnologie groot potensiaal bied om vervoer- en aktiwiteitsgedragnavorsings aan te vul en verder uit te bou. Verder toon die resultate dat die inkorporering van ruimtelike en temporale metings van kritieke belang is vir die ontwerp, implementering en evaluering van VRGV-intervensies. Die bykomende waarde van nuwe tegnologieë, soos GPS, is dat hulle maklik in 'n groter ruimtelike-temporale raamwerk van analise geïntegreer kan word. Navorsers moet egter versigtig wees om nie GPS as 'n wondermiddel te beskou nie want GPS-data en tegnologie het ook nadele. Omsigtigheid behoort aan die dag gelê te word ten opsigte van toepassingsontwikkeling, steekproef seleksie, terreinkeuse en data afleidings.
Description
Thesis (PhD)--Stellenbosch University, 2017.
Keywords
Global Positioning System (GPS), Geographic information systems (GIS), Voluntary travel behaviour change (VTBC), Smartphones, Time geography, UCTD
Citation