James Cheshire

Health effects of the London bicycle sharing system: health impact modelling study.

Objective To model the impacts of the bicycle sharing system in London on the health of its users. Design Health impact modelling and evaluation, using a stochastic simulation model. Setting Central and inner London, England. Data sources Total population operational registration and usage data for the London cycle hire scheme (collected April 2011-March 2012), surveys of cycle hire users (collected 2011), and London data on travel, physical activity, road traffic collisions, and particulate air pollution (PM2.5, (collected 2005-12). Participants 578 607 users of the London cycle hire scheme, aged 14 years and over, with an estimated 78% of travel time accounted for by users younger than 45 years. Main outcome measures Change in lifelong disability adjusted life years (DALYs) based on one year impacts on incidence of disease and injury, modelled through medium term changes in physical activity, road traffic injuries, and exposure to air pollution. Results Over the year examined the users made 7.4 million cycle hire trips (estimated 71% of cycling time by men). These trips would mostly otherwise have been made on foot (31%) or by public transport (47%). To date there has been a trend towards fewer fatalities and injuries than expected on cycle hire bicycles. Using these observed injury rates, the population benefits from the cycle hire scheme substantially outweighed harms (net change −72 DALYs (95% credible interval −110 to −43) among men using cycle hire per accounting year; −15 (−42 to −6) among women; note that negative DALYs represent a health benefit). When we modelled cycle hire injury rates as being equal to background rates for all cycling in central London, these benefits were smaller and there was no evidence of a benefit among women (change −49 DALYs (−88 to −17) among men; −1 DALY (−27 to 12) among women). This sex difference largely reflected higher road collision fatality rates for female cyclists. At older ages the modelled benefits of cycling were much larger than the harms. Using background injury rates in the youngest age group (15 to 29 years), the medium term benefits and harms were both comparatively small and potentially negative. Conclusion London’s bicycle sharing system has positive health impacts overall, but these benefits are clearer for men than for women and for older users than for younger users. The potential benefits of cycling may not currently apply to all groups in all settings.

People of the British Isles: preliminary analysis of genotypes and surnames in a UK-control population

There is a great deal of interest in a fine-scale population structure in the UK, both as a signature of historical immigration events and because of the effect population structure may have on disease association studies. Although population structure appears to have a minor impact on the current generation of genome-wide association studies, it is likely to have a significant part in the next generation of studies designed to search for rare variants. A powerful way of detecting such structure is to control and document carefully the provenance of the samples involved. In this study, we describe the collection of a cohort of rural UK samples (The People of the British Isles), aimed at providing a well-characterised UK-control population that can be used as a resource by the research community, as well as providing a fine-scale genetic information on the British population. So far, some 4000 samples have been collected, the majority of which fit the criteria of coming from a rural area and having all four grandparents from approximately the same area. Analysis of the first 3865 samples that have been geocoded indicates that 75% have a mean distance between grandparental places of birth of 37.3 km, and that about 70% of grandparental places of birth can be classed as rural. Preliminary genotyping of 1057 samples demonstrates the value of these samples for investigating a fine-scale population structure within the UK, and shows how this can be enhanced by the use of surnames.

The Family Name as Socio-Cultural Feature and Genetic Metaphor: From Concepts to Methods

Abstract A recent workshop entitled “The Family Name as Socio-Cultural Feature and Genetic Metaphor: From Concepts to Methods” was held in Paris in December 2010, sponsored by the French National Centre for Scientific Research (CNRS) and by the journal Human Biology. This workshop was intended to foster a debate on questions related to the family names and to compare different multidisciplinary approaches involving geneticists, historians, geographers, sociologists and social anthropologists. This collective paper presents a collection of selected communications.

Delineating Europe's Cultural Regions: Population Structure and Surname Clustering

Abstract Surnames (family names) show distinctive geographical patterning and in many disciplines remain an underutilized source of information about population origins, migration and identity. This paper investigates the geographical structure of surnames, using a unique individual level database assembled from registers and telephone directories from 16 European countries. We develop a novel combination of methods for exhaustively analyzing this multinational data set, based upon the Lasker Distance, consensus clustering and multidimensional scaling. Our analysis is both data rich and computationally intensive, entailing as it does the aggregation, clustering and mapping of 8 million surnames collected from 152 million individuals. The resulting regionalization has applications in developing our understanding of the social and cultural complexion of Europe, and offers potential insights into the long and short-term dynamics of migration and residential mobility. The research also contributes a range of methodological insights for future studies concerning spatial clustering of surnames and population data more widely. In short, this paper further demonstrates the value of surnames in multinational population studies and also the increasing sophistication of techniques available to analyze them.

Cities as Flows, Cities of Flows

One of the key differences between theories of cities developed a half century or more ago and the emerging science of cities and societies in the early 21st century revolves around the idea that our focus should no longer be on location, but on interactions and connections, on networks and the concomitant processes that define flows between places and spaces. In one sense, this changing focus is recognition that location is simply a manifestation of ways in which people agglomerate so that they can communicate with one another. By peeling back the locational layer, we begin to see how cities really function as sets of interactions that flow across networks: some physical and visible but many relational, social, and often invisible. Although the network paradigm now represents the cutting edge to new representations and models in many fields, a calculus for handling ways in which interactions relate to locations has barely emerged. Fifty years ago spatial interaction theory developed to show us how flows (usually of physical traffic) could be synthesised into volumes of activity defining locations. There was little emphasis then on the network morphology that provided the infrastructure for such flows but, in the last decade, network science has provided a powerful theory and practice for describing the properties of networks; yet developments have largely avoided embedding flows into the arcs and nodes that define the graphs used in their modelling. The telling point is that flows are often regarded as weights to be placed on networks and this discourages any thinking that might give precedence to flows over the networks that they occupy. Indeed, it is an obvious point that the interaction between networks and flows is complicated, with flow volumes forcing changes in network topology and vice versa. The problem is that flows and networks tend to be treated in too narrow a fashion. A calculus of interaction or connection must begin not with interactions per se but with notions about changes between locations that in themselves define flows through time. Dynamics (and hence motion) is absolutely essential to any theory of flows in cities and it is worth generalising this to the point where any kind of change might be treated as a flow, from physical, social, or electronic transactions through to changes caused by aging, regeneration, economic growth, and so on. In fact, the long-standing notion in macroeconomics of defining the economy in terms of stocks and flows is the nearest we have to suggesting a rather general kind of dynamics relating to flow. Systems Dynamics developed by Forrester (1961) defines all change as being composed of flows that integrate or sum to stocks. In spatial interaction, stocks can be seen as integrations or summations of flows that take place between origins and destinations. Two conceptual viewpoints are often adopted in dynamics. First, motion can be described at fixed locations where changes that take place are observed and recorded. In contrast, a second approach considers motion with respect to how an attribute or component changes with respect to different locations; the observation and measurement being rooted in the trajectory of the object itself. The first approach is sometimes called the Eulerian frame of reference, a bit like watching a place change as people come and go. In contrast, the second, the Lagrangian frame of reference, is more like watching a person travelling through time from place to place. This is a neat distinction. But to get some real perspective on how a system changes we need both frames. A theory of flows, however, must define motion more generically than this. Location and Editorial Environment and Planning B: Planning and Design 2011, volume 38, pages 195 ^ 196

The Surname Regions of Great Britain

Abstract Please click here to download the map associated with this article. The British Population retains a strong sense of regional identity, epitomized by periodic campaigns for Scottish and Welsh devolution, or for Cornish self-government. There have been few studies into the regionalization of British surnames and none that utilize any register that can claim to be nationally representative. The National Social Map presented in this paper is the first comprehensive attempt to create a regional geography of Great Britain based upon the clustering of surnames. The resulting map illustrates a strong relationship between the populations surnames and geographic location. The homogeneity within each of the surname regions identified is striking given that spatial contiguity constraints were not included within the clustering process. The map will hopefully set a bench-mark for future work by geographers in the field of surname research.

Interactive mapping for large, open demographic data sets using familiar geographical features

ABSTRACT Ever-increasing numbers of large demographic data sets are becoming available. Many of these data sets are provided as open data, but are in basic repositories where it is incumbent on the user to generate their own visualisations and analysis in order to garner insights. In a bid to facilitate the use and exploration of such data sets, we have created a web mapping platform called DataShine. We link data from the 2011 Census for England and Wales with open geographical data to demonstrate the power and utility of creating a conventional map and combining it with a simple but flexible interface and a highly detailed demographic data set.

The Surname Space of the Czech Republic: Examining Population Structure by Network Analysis of Spatial Co-Occurrence of Surnames

In the majority of countries, surnames represent a ubiquitous cultural attribute inherited from an individuals ancestors and predominantly only altered through marriage. This paper utilises an innovative method, taken from economics, to offer unprecedented insights into the “surname space” of the Czech Republic. We construct this space as a network based on the pairwise probabilities of co-occurrence of surnames and find that the network representation has clear parallels with various ethno-cultural boundaries in the country. Our inductive approach therefore formalizes a simple assumption that the more frequently the bearers of two surnames concentrate in the same locations the higher the probability that these two surnames can be related (considering ethno-cultural relatedness, common co-ancestry or genetic relatedness, or some other type of relatedness). Using the Czech Republic as a case study this paper offers a fresh perspective on surnames as a quantitative data source and provides a methodology that can be easily incorporated within wider cultural, ethnic, geographic and population genetics studies already utilizing surnames.

Deriving retail centre locations and catchments from geo-tagged Twitter data

This investigation offers an initial foray into the application of geo-tagged Twitter data for generating insights within two areas of retail geography: establishing retail centre locations and defining catchment areas. Retail related Tweets were identified and their spatial attributes examined with an adaptive kernel density estimation, revealing that retail related Twitter content can successfully locate areas of elevated retail activity, however, these are constrained by biases within the data. Methods must also account for the underlying geographic distribution of Tweets to detect these fluctuations. Additionally, geo-tagged Twitter data can be utilised to examine human mobility patterns in a retail centre context. The catchments constructed from the data highlight the importance of accessibility on flows between locations, which have implications for the likely commuting choices that may be involved in retail centre journey decision-making. These approaches demonstrate the potential applications for less conventional datasets, such as those derived from social media data, to previously under-researched areas.

Analysing surnames as geographic data.

With most surname research undertaken within the fields of anthropology and population genetics, geographers have overlooked surnames as a credible data source. In addition to providing a review of recent developments in surname analysis, this paper highlights areas where geographers can make important contributions to advancing surname research, both in terms of its quality and also its applications. The review discusses the emerging applications for surname research, not least in the mining of online data, and ends by suggesting three future research themes to ensure the building momentum of surname research continues to grow across disciplines.