Using Bikeshare Datasets to Improve Urban Cycling Experience and Research Urban Cycling Behaviour

With access to public and shared transport systems becoming increasingly digitized, transaction datasets of unprecedented size as well as temporal and spatial precision are automatically generated (Blythe and Bryan 2007; Bagchi and White 2005; Pelletier et al. 2011). Data collected through smartcard payment methods are perhaps the largest and most obvious example. Although introduced for the purpose of improving payment processes, such data provide a detailed view of demand on a transport system, the potential for service improvements to be suggested (Ferrari et al. 2014) and an opportunity for studying individual traveller behaviour (Agard et al. 2006; Morency et al. 2006; Lathia et al. 2013). A substantial benefit of such data over more traditional data collection methods is that a complete and total record of usage for every smartcard customer is automatically generated (Bagchi and White 2005). Problems associated with sampling and recall bias, which make actively collected travel surveys somewhat difficult to administer, are avoided. The two most obvious disadvantages, at least for travel behaviour research, are that those individuals using smartcard technology may not be representative of the total population using that system or navigating a city more generally; and that variables such as individual trip purpose can only be inferred since they are not recorded directly

Discovery exhibition: using spatial treemaps in local authority decision making and reporting

At Leicestershire County Council we are using spatial treemaps to analyse labour markets and commuting behaviour. This novel visualization technique, presented at InfoVis 2008, has resulted in a number of insights and discoveries. Transport planners in our organization indicate that the graphics are effective and have advantages over alternatives. As researchers in the local authority we report upon using these graphics to inform decision makers and residents in the county’s evidence base for sustainable transport planning

Characterising labour market self-containment in London with geographically arranged small multiples

We present a collection of small multiple graphics that support analysis and understanding of the geography of labour-market self-containment across London’s 33 boroughs. Ratios describing supply-side self-containment, the extent to which working residents access jobs locally, and demand-side self-containment, the extent to which local jobs are filled by local resident workers, are first calculated for professional and non-professional occupations and encoded directly through geographically-arranged bar charts. The full distribution of workers into-and out-of- boroughs that underpins these ratios is then revealed via Origin-Destination flows maps (OD maps) – sets of geographically-arranged choropleths. In order to make relative and absolute comparison of borough-to-borough frequencies between occupation types, these OD maps are coloured according to signed chi-square residuals: for every borough-to-borough pair, we compare the observed number of flows to access professional versus non-professional jobs against the number that would be expected given the distribution of those jobs across London boroughs. Our geographically-arranged small multiples demonstrate potential for spatial analysis: a rich, multivariate structure is depicted that reflects London’s economic geography and that would be difficult to expose using non-visual means

Towards confirmatory data analysis? Deriving and analysing routing information for an origin-destination bike share dataset

Data collected from urban bike share schemes allow observed travel behaviours to be analysed on a uniquely large scale. Exploring such timed origin-destination (OD) data from the London Cycle Hire Scheme (LCHS), we previously generated detailed insights into spatiotemporal patterns of travel and suggested new hypotheses for their motivation. A limitation was that with only the origins and destinations of cycle journeys, little was known about the nature and context of likely cycled routes. In this study, we use the CycleStreets routing engine to derive routing information for every OD pair made through the LCHS. From these suggested routes, we collect heuristics for the nature of each journey. Information on the number of signalled junctions encountered, on any bridges crossed, as well as a proxy for the busyness of suggested routes is recorded. We then analyse over 5 million journeys made by LCHS members during a 12-month period (September 2011 – September 2012). Focussing on LCHS journeys that involve crossing the River Thames, we observe differences in male and female cyclists’ apparent use of bridges, which appear to be strongly related to a commuting function. Studying heuristics of suggested routes over these bridges, we find some evidence to suggest that women may be underrepresented amongst commuting journeys that involve a river crossing because those very journeys are associated with relatively busy and demanding routes. We also find evidence that the nature of frequently cycled journeys involving a river crossing might explain imbalances in the direction of journeys made over the river when we select periods of more discretionary activity – when studying weekend journeys. These findings are nevertheless quite speculative. A number of confounders cannot be easily accounted for within this analysis: the economic geography of the city, spatial interactions between docking stations at particular space-times and the relative availability of transport alternatives. Perhaps most importantly, our analysis assumes that routes suggested by the routing algorithm closely reflect individuals’ actually cycled routes

Characterising group-cycling journeys using interactive graphics

The group-cycling behaviours of over 16,000 members of the London Cycle Hire Scheme (LCHS), a large public bikeshare system, are identified and analysed. Group journeys are defined as trips made by two or more cyclists together in space and time. Detailed insights into group-cycling behaviour are generated using specifically designed visualization software. We find that in many respects group-cycle journeys fit an expected pattern of discretionary activity: group journeys are more likely at weekends, late evenings and lunchtimes; they generally take place within more pleasant parts of the city; and between individuals apparently known to each other. A separate set of group activity is found, however, that coincides with commuting peaks and that appears to be imposed onto LCHS users by the scheme's design. Studying the characteristics of individuals making group journeys, we identify a group of less experienced LCHS cyclists that appear to make more spatially extensive journeys than they would do normally while cycling with others; and that female cyclists are more likely to make late evening journeys when cycling in groups. For 20% of group cyclists, the first journey ever made through the LCHS was a group journey; this is particularly surprising since just 9% of all group cyclists' journeys are group journeys. Moreover, we find that women are very significantly (p<0.001) overrepresented amongst these `first time group cyclists'. Studying the bikeshare cyclists, or bikeshare `friends', that individuals make `first time group journeys' with, we find a significantly high incidence (p<0.001) of group journeys being made with friends of the opposite gender, and for a very large proportion (55%) of members these first ever journeys are made with a friend that shares the same postcode. A substantial insight, then, is that group cycling appears to be a means through which early LCHS usage is initiated

Performance criteria for multi-sourced urban water systems

Urban water management is now constrained by rapid population growth, climate change and variability and their prediction uncertainty and above all by resource limitations. The ability of water systems to operate satisfactorily under these constraints is an important system characteristic. Performance criteria described in terms of mean yield and variance are not sufficient. Therefore risk-based performance criteria for urban water systems are proposed. These criteria are risk and reliability, resiliency and vulnerability. The quantitative estimation of these criteria and their implications for water resources planning are expected to improve the long term sustainability of water systems. The relatively new concept of integrated urban water management encourages water source diversification. This includes the use of rainwater, stormwater and treated wastewater. In this paper, multi-sourced urban water systems and their risk-based performance criteria have been proposed

Monitoring the Health of Computer Networks with Visualization - VAST 2012 Mini Challenge 1 Award: "Efficient Use of Visualization"

The complex computer networks of large organisations contain many machines of many types, used in many geographic locations. Although system administrators should monitor the health of each machine, they need to do so within the context of the whole computer network. Our visualization presents the health of a fictitious financial institution's computer network at a snapshot in time and over a time range, and preserves the important aspects of each facility's administrative and geographic context. Using the "Bank of Money" VAST Challenge dataset, our visualization allowed us to correctly identify several areas of concern, as well as hypothesise about their causes

Moving beyond sequential design: Reflections on a rich multi-channel approach to data visualization

We reflect on a four-year engagement with transport authorities and others involving a large dataset describing the use of a public bicycle-sharing scheme. We describe the role visualization of these data played in fostering engagement with policy makers, transport operators, the transport research community, the museum and gallery sector and the general public. We identify each of these as ‘channels’ – evolving relationships between producers and consumers of visualization – where traditional roles of the visualization expert and domain expert are blurred. In each case, we identify the different design decisions that were required to support each of these channels and the role played by the visualization process. Using chauffeured interaction with a flexible visual analytics system we demonstrate how insight was gained by policy makers into gendered spatio-temporal cycle behaviors, how this led to further insight into workplace commuting activity, group cycling behavior and explanations for street navigation choice. We demonstrate how this supported, and was supported by, the seemingly unrelated development of narrative-driven visualization via TEDx, of the creation and the setting of an art installation and the curating of digital and physical artefacts. We assert that existing models of visualization design, of tool/technique development and of insight generation do not adequately capture the richness of parallel engagement via these multiple channels of communication. We argue that developing multiple channels in parallel opens up opportunities for visualization design and analysis by building trust and authority and supporting creativity. This rich, non-sequential approach to visualization design is likely to foster serendipity, deepen insight and increase impact