Social Space and Social Media: Analyzing Urban Space with Big Data

This dissertation focuses on the key role that big data can play in minimizing the perceived disconnect between social theory and quantitative methods in the discipline of geography. It takes as its starting point the geographic concept of space, which is conceptualized very differently in social theory versus quantitative methodology. Contrary to this disparity, an examination of the disciplinary history reveals a number of historic precedents and potential pathways for a rapprochement, especially when combined with some of the new possibilities of big data. This dissertation also proposes solutions to two common barriers to the adoption of big data in the social sciences: accessing and collecting such data and, subsequently, meaningful analysis. These methods and the theoretical foundation are combined in three case studies that show the successful integration of a quantitative research methodology with social theories on space. The case studies demonstrate how such an approach can create new and alternative understandings of urban space. In doing so it answers three specific research questions: (1) How can big data facilitate the integration of social theory on space with quantitative research methodology? (2) What are the practical challenges and solutions to moving “beyond the geotag” when utilizing big data in geographical research? (3) How can the quantitative analysis of big data provide new and useful insight in the complex character of social space? More specifically, what insights does such an analysis of relational social space provide about urban mobility and cognitive neighborhoods

Attentional Social Media: Mapping the Spaces and Networks of the Fashion Industry

In this article we use big data methods to analyze the attention paid to the fashion industry on social media. The article argues that for the fashion industry, like many industries, the core product is a form of knowledge that is dependent on gaining and holding people’s attention. To understand this attentional economy, social media offers a unique window because it is increasingly a central space within which fashion knowledge is created and shared. Using long-term, geotagged big data from Twitter, we analyze the hitherto difficult-to-explore spaces and places of the global fashion industry. The article suggests that the data confirm the ideas that there are a series of global fashion capitals that are especially important to the industry and that attention paid to fashion is highly uneven and varied across industry functions, national origins, and companies. Evidence is presented that attention to fashion is a global phenomenon that does not always directly link to where fashion products are sold. Attention to fashion is both a market-making mechanism for the industry as well as an indicator of wider social and cultural processes of tastemaking and identity formation within which fashion is entwined. The article concludes by suggesting that such data offer geographers new ways of looking at and linking economic, social, and cultural spaces and geographies and that social media analysis can help bridge boundaries that divide geographers

Christaller and “big data”: recalibrating central place theory via the geoweb

This article utilizes central place theory (CPT) to navigate the “deluge” brought about by big data. While originating in the 1930s, CPT is a theoretical monument of 1960s spatial science. CPT aims to understand settlement geographies based on consumption behavior and is often presented as a singular, outdated, and rationalist theory. After critically reviewing the history of CPT, we assess the microfoundations of Christaller’s CPT–the threshold and range of goods–for various central functions in Louisville, Kentucky. The microfoundations are estimated through data from social media platforms Foursquare and Twitter. These sources alleviate many of the operationalization issues that traditionally hamper empirical use of CPT. The empirical application of CPT reveals that: (i) central functions have typical ranges and thresholds relating central places to population spread; (ii) central functions cluster based on an approximate hierarchical structure. The findings indicate the ongoing importance of CPT in shaping urban-economic geographies

Challenges When Identifying Migration from Geo-Located Twitter Data

Given the challenges in collecting up-to-date, comparable data on migrant populations the potential of digital trace data to study migration and migrants has sparked considerable interest among researchers and policy makers. In this paper we assess the reliability of one such data source that is heavily used within the research community: geolocated tweets. We assess strategies used in previous work to identify migrants based on their geolocation histories. We apply these approaches to infer the travel history of a set of Twitter users who regularly posted geolocated tweets between July 2012 and June 2015. In a second step we hand-code the entire tweet histories of a subset of the accounts identified as migrants by these methods. Upon close inspection very few of the accounts that are classified as migrants appear to be migrants in any conventional sense or international students. Rather we find these approaches identify other highly mobile populations such as frequent business or leisure travellers, or people who might best be described as “transnationals”. For demographic research that draws on this kind of data to generate estimates of migration flows this high mis-classification rate implies that findings are likely sensitive to the adjustment model used. For most research trying to use these data to study migrant populations, the data will be of limited utility. We suspect that increasing the correct classification rate substantially will not be easy and may introduce other biases

Pacifying Babel’s Tower: A scientometric analysis of polycentricity in urban research

It is sometimes claimed that the degree of polycentricity of an urban region influences that region’s competitiveness. However, because of widespread use and policy relevance, the underlying concept of polycentricity has become a ‘stretched concept’ in urban studies. As a result, academic debate on the topic leads to situations reminiscent of Babel’s Tower. This meta-study of the scientific literature in urban studies traces the conceptual stretching of polycentricity using scientometric methods and content analysis. All published studies that either apply the concept directly or cite a work that does, were collected from the Scopus bibliographic database. This resulted in a citation network with over 9000 works and more than 20,000 citations between them. Network analysis and clustering algorithms were used to define the most influential papers in different citation clusters within the network. Subsequently, we employed content analysis to systematically assess the mechanisms associated with the formation of polycentric urban systems in each of these papers. Based on this meta-analysis, we argue that the common categorisation of polycentricity research in intra-urban, inter-urban and inter-regional polycentricity is somewhat misleading. More apt categorisations to understand the origins of polycentricity’s conceptual ambiguity relate to different methodological traditions and geographical contexts in which the research is conducted. Nonetheless, we observe a firm relation across clusters between assessments of polycentricity and different kinds of agglomeration economies. We conclude by proposing a re-conceptualisation of polycentricity based on explicitly acknowledging the variable spatial impact of these different kinds of agglomeration economies

Containment and Connectivity in Dutch Urban Systems: A Network‐Analytical Operationalisation of the Three‐Systems Model

This paper discusses key methodological issues with nodalising interaction data of urban networks to produce a state-of-the-art settlement geography of the Netherlands. We operationalise the threesystems model that analyses functional settlement geographies through the interaction between the daily urban system, the central place system and the export base system. We utilise theoreticallyinformed selections of spatial interactions derived from travel survey data at the finely-grained postcode level. After examining the methodological challenge of the node-inclusivity dilemma, we estimate the causal mechanisms that geographically structure each system and determine which spatial interactions should be assigned to nodes (containment) and edges (connectivity). The three systems produce different regionalisations that are neither mutually exclusive nor perfectly nested. Further analysis of the multiplexity of the three systems reveals the importance of the imbricated boundaries between the urban subsystems. We argue that these interplaces deserve more attention as they are particularly sensitive to changes in urbanisation trends

Containment and Connectivity in Dutch Urban Systems: A Network‐Analytical Operationalisation of the Three‐Systems Model

This paper discusses key methodological issues with nodalising interaction data of urban networks to produce a state-of-the-art settlement geography of the Netherlands. We operationalise the threesystems model that analyses functional settlement geographies through the interaction between the daily urban system, the central place system and the export base system. We utilise theoreticallyinformed selections of spatial interactions derived from travel survey data at the finely-grained postcode level. After examining the methodological challenge of the node-inclusivity dilemma, we estimate the causal mechanisms that geographically structure each system and determine which spatial interactions should be assigned to nodes (containment) and edges (connectivity). The three systems produce different regionalisations that are neither mutually exclusive nor perfectly nested. Further analysis of the multiplexity of the three systems reveals the importance of the imbricated boundaries between the urban subsystems. We argue that these interplaces deserve more attention as they are particularly sensitive to changes in urbanisation trends

Moving the 15-minute city beyond the urban core: The role of accessibility and public transport in the Netherlands

The 15-minute city – providing every resident\u27s daily needs within a 15-minute walk, cycle or public transportation ride – has recently gained popularity among policy makers as a means for a more sustainable and just future. While the goal of a more equitable and sustainable city is laudable, we note that half of the world\u27s population (still) lives in non-urban areas and thus seek to explore how the concept of the 15-minute city might extend into suburbs, exurbs and even the countryside. We do this via an empirical analysis of 16 years of travel survey data in the Netherlands and evaluate the relevance of the 15-minute city concept in non-urban areas. We frame our analysis via three specific aspects of the 15-minute concept: (i) differences in reliance on cars in urban and non-urban areas; (ii) differences in extra travel time across the urban-rural continuum if all car-based trips were replaced by public transport; and (iii) the effect of accessibility of goods and services on extra travel time if all car-based trips were replaced by public transport. Based on our findings, we argue that practical implementations of the 15-minute city (focused on the urban core) risk missing the particular challenges facing non-urban neighborhoods, especially in terms of car reliance. As planners rush to address the affordable housing crisis in the Netherlands and elsewhere, these short-comings highlight the importance of expanding research and policy practice in terms of scope (i.e. including non-urban areas) and focus (i.e. considering other reasons for individual travel beyond goods and services) to better reflect the lived experience of people across all geographies

Containment and Connectivity in Dutch Urban Systems: A Network‐Analytical Operationalisation of the Three‐Systems Model

This paper discusses key methodological issues with nodalising interaction data of urban networks to produce a state-of-the-art settlement geography of the Netherlands. We operationalise the threesystems model that analyses functional settlement geographies through the interaction between the daily urban system, the central place system and the export base system. We utilise theoreticallyinformed selections of spatial interactions derived from travel survey data at the finely-grained postcode level. After examining the methodological challenge of the node-inclusivity dilemma, we estimate the causal mechanisms that geographically structure each system and determine which spatial interactions should be assigned to nodes (containment) and edges (connectivity). The three systems produce different regionalisations that are neither mutually exclusive nor perfectly nested. Further analysis of the multiplexity of the three systems reveals the importance of the imbricated boundaries between the urban subsystems. We argue that these interplaces deserve more attention as they are particularly sensitive to changes in urbanisation trends

Urban governance and electricity losses: An exploration of spatial unevenness in Karachi, Pakistan

Ministry of Education, Singapore under its Academic Research Funding Tier