This thesis comprises four essays in the economics of networks and market design. The common thread in all these essays is the presence of complementarities or externalities. Chapter 2 presents a unified model of networks and matching markets. We build on a contribution by Pycia (2012). We show that strong pairwise alignment of agents’ preferences is a necessary and sufficient condition for the existence of strongly stable networks and strongly stable allocations in multilateral matching markets with finite contracts. Strongly stable networks are not necessarily efficient. Although we use a demanding stability concept, strong pairwise alignment allows for complementarities and externalities. In Chapter 3, we generalise the gross substitutes and complements condition introduced by Sun and Yang (2006). Our new condition guarantees the existence of competitive equilibrium in economies with indivisible goods. Competitive equilibrium can be found using an extension of the double-track adjustment process (Sun and Yang, 2009). In this chapter, we also study contract networks (Ostrovsky, 2008). We show that chain-stable contract allocations can exist even in cyclical contractual networks, such as electricity markets, as long as they are appropriately segmented. In Chapter 4, we run a series of experiments to compare the performance of four auctions – first-price, Vickrey, Vickrey-Nearest Rule (Day and Cramton, 2008), and Reference Rule (Erdil and Klemperer, 2010). In our setting, there are two items and three bidders. Two local bidders want an item each, but the global bidder wants both items. We introduce various exposure and package-bidding treatments. We find that the first-price auction always revenue-dominates all the other auctions without any loss in efficiency, strengthening the results of Marszalec (2011). Exposure affects global bidders only in the first-price auction. In other auctions, global bidders often do not take into account the effect of their own bids on their payments. We find no evidence of threshold effects. Finally, in Chapter 5, we develop a new model of online social network formation. In this model, agents belong to many overlapping social groups. We derive analytical solutions for the macroscopic properties of the network, such as the degree distribution. We study the dynamics of homophily – the tendency of individuals to associate with those similar to themselves. We calibrate our model to Facebook data from ten American colleges.

This research was initiated by questions raised from the researcher’s professional activities in fine art printmaking and examines, through contextualised artistic practice and critical enquiry, redefinitions in the physical and temporal parameters of digitally mediated fine art printmaking caused by developments in digital media; specifically the impact of digital culture, Web2.0, social networking, augmented and virtual reality. Grounded on critical contextual review the research explores, through contextualised research probes, the notion of post-physical practice and the impact of new modes of collaboration, distribution and consumption on contemporary printmaking. It includes the findings of an international, digitally mediated, participatory and collaborative exchange survey of contemporary digital print, developed through direct enquiry using social media as a research tool. Philosophical questions about the impact of eculture, post-physical working and new modes of print-based artistic practice were examined, as well as the indexicality of the print itself in augmented and virtual contexts. The research employs dynamic triangulation between critical contextual review and direct qualitative and practice-based research; to develop a taxonomy framing the contextual precedents of digital printmaking, pinpointing key markers of transition between traditional and new printmaking. It uses post-studio methods and explores the conception, production, editioning, collection and ownership of print in an increasingly networked digital age, providing proof of concept and exploring virtual immersive surfaces in printmaking. These lead to the development of new models for a second generation of printmaking practice or Printmaking2.0 expressly founded in post-physical practice in a poststudio context and embracing the lingua franca of contemporary digital practice in the production of born digital virtually imprinted forms. In both, the technical practice of post-physical printmaking and the significant artistic implications resulting from the cultural shifts following digital participation and post-physical embodiment.

Agglomerative Clustering techniques work by recursively merging graph vertices into communities, to maximize a clustering quality metric. The metric of Modularity coined by Newman and Girvan, measures the cluster quality based on the premise that, a cluster has collections of vertices more strongly connected internally than would occur from random chance. Various fast and efficient algorithms for community detection based on modularity maximization have been developed for static graphs. However, since many (contemporary) networks are not static but rather evolve over time, the static approaches are rendered inappropriate for clustering of dynamic graphs. Modularity optimization in changing graphs is a relatively new field that entails the need to develop efficient algorithms for detection and maintenance of a community structure while minimizing the “Size of change” and computational effort. The objective of this work was to develop an efficient dynamic agglomerative clustering algorithm that attempts to maximize modularity while minimizing the “size of change” in the transitioning community structure. First we briefly discuss the previous memoryless dynamic reagglomeration approach with localized vertex freeing and illustrate its performance and limitations. Then we describe the new backtracking algorithm followed by its performance results and observations. In experimental analysis of both typical and pathological cases, we evaluate and justify various backtracking and agglomeration strategies in context of the graph structure and incoming stream topologies. Evaluation of the algorithm on social network datasets, including Facebook (SNAP) and PGP Giant Component networks shows significantly improved performance over its conventional static counterpart in terms of execution time, Modularity and Size of Change.

This paper investigates how social networks act as catalysts for innovation. It borrows a model for understanding how interaction between heterogeneous social networks catalyzes innovation. Using this model, it then examines historical and contemporary catalysts of innovation and invention within cities. Industry diversity, a measure representing the existence of multiple overlapping domains, is hypothesized to be positively correlated with the number of patents filed within a city per year. Using this analysis of both Renaissance Florence and contemporary metropolitan areas, the paper hopes to demonstrate social influences on innovation.

Geographical regions as diverse as Silicon Valley, California and Linköping, Sweden have been the sources of new technology and endogenously created innovations. Scholars and policymakers recognise that specific regions or clusters of businesses have the capability to engage in more innovative activities and new business formation and to experience higher employment growth than others. This dissertation uses qualitative methods to study various aspects of regional development and innovation. It is based on five papers by the author and colleagues with levels of analysis ranging from regional to firms’ first sales in order to capture the dynamics of both the top and bottom levels of regional development. It then uses these papers’ empirical material to address the research questions of (a) how a new scientific knowledge base becomes established and exploited in a spatial context, and (b) how people create and diffuse innovations in a social and spatial context. This dissertation’s main findings are that (a) regional leadership involving the building of alliances with triple-helix actors is crucial for initiating a knowledge-based regional development process, (b) a consensus space is a catalytic mechanism for ensuring the speed and effectiveness of regional development, (c) lowering the barriers for the actors involved boosts participation and the rate of innovation, and (d) users’ perspectives are essential for social, institutional and commercial innovation. This dissertation’s main implications are that knowledge-based regional development’s initial stages require leadership that (a) builds alliances and establish an arena for the triple-helix actors, (b) analyses the regional barriers to the commercialisation of knowledge, and (c) utilises both endogenous and exogenous resources. / Kännetecknande för regioner som Silicon Valley, och även Linköping, medstark närvaro av kunskapsproducerande aktörer, som ett universitet, är att det frekventoch kontinuerligt genereras nya teknologier som utgör grunden för innovationer ochaffärsmöjligheter. Under de senaste tjugo åren har det från policysynpunkt funnits ettstort intresse hur vida man kan stimulera kunskapsbaserad regional utveckling i formav exempelvis nya universitetssatsningar, riskkapitalinitiativ ochentreprenörskapsprogram. I den här avhandlingen studeras dynamiken i kunskapsbaserad regionalutveckling och innovation. Av särskilt intresse är framväxten av en ny kunskapsbas ien region och dess möjlighet att generera innovationer. Där av avhandlingens tvåfrågeställningar: (a) Hur etableras en ny kunskapsbas sett ur en regional kontext? (b)Hur skapas och sprids innovationer inom en social och spatial kontext? Avhandlingen har en kvalitativ ansats med fallstudier som metod. Fem bidragutgör basen för själva avhandlingen. I huvudsak genereras följande slutsatser vilka ärcentrala för att förstå själva problematiken i kunskapsbaserad regional utveckling: (a)Närvaro av regionalt ledarskap med en triple helix orientering är centralt förkunskapsbaserad regional utveckling. (b) En arena för samförstånd bidrar till snabbareoch mer effektiv utveckling. (c) Det finns barriärer i kommersialiseringsprocessen avden nya kunskapen, exempelvis svårigheter för aktörer med ett problem och aktörermed lösningar att finna varandra, som hindrar utvecklingen. (d) Användarperspektivetfinns i alla typer av innovationer; kommersiella, institutionella, och sociala. De främsta implikationer för praktiker baserat på den här avhandlingen är attför att etablera en kunskapsbaserad regional utvecklingsprocess krävs ett ledarskapsom (a) kan bygga allianser med andra triple helix aktörer och skapa en arena församstånd, (b) kan förstå vilka barriärer för kommersialisering som finns och (c) kananvända sig av både endogena och exogena resurser.

This research develops a theoretical framework explaining how University-Industry Linkages (UILs) affect the performance of tourism clusters in Thailand. Significant external and internal factors affecting Thai tourism industry are examined. The research questions are significant given the importance of successful tourism cluster through University-Industry Linkages (UIL). These questions recognized tourism clusters, the role of university, the linkages between university and industry, influential factors are contextual, and as a result, the author explores four tourism clusters in Thailand and using multiple case studies explains the nature and character of tourism cluster and University-Industry Linkages (UILs) between tourism cluster and its universities. The findings demonstrated that UILs, strategic entrepreneurship and leadership play key role to successful tourism cluster in developing countries.

Thesis (MBA)--Stellenbosch University, 2011. / The purpose of this study is to identify the user features for an online sports community network. Social networks sites are on a rapid increase. Designers of these sites need to consider what features are critical to optimally facilitate their users’ behaviour on these sites. This identification of features will seek to enhance the growth and development of a site’s social communities and allow for its ultimate success. This study focuses on establishing the social networking ecosystem by identifying the role of social networks in society, the user behaviour trends on social network sites and the key features required for a social network site. Furthermore, the study establishes the role of sports fans in society and digital trends for online sports fans visiting sports sites. This study met the research objectives from the findings gained from relevant literature and the employment of an empirical research study. The latter was carried out by means of an online questionnaire targeting an audience that qualified to be both social media lovers and online sports fans. The research disclosed fundamental findings with regards to the user behaviour and frequency of usage of both social network sites and sports sites. Specifically, it was determined that the technological behaviours in the social technographic profile for online users were aligned to those of the social technographic profile for social media lovers and online sports fans. Consequently, the key features of social network sites and most frequently-used features on sports sites could be used to identify the features required for an online sports community network. The main conclusion drawn from this research was a list of features required for a sports community network. These features were determined for the initial launch phase of a sports community network. Enhancement and development of new features would be required to facilitate the user requirements as the site grows. It is therefore important for the success of the sports community site that the owners or designers continuously review the user requirements and adapt, enhance and develop features as the site gains traction. This research study recommends that the list provided be used for the initial design and launch phase of an online sports community network. This list should be constantly evaluated from a usercentric perspective as the site grows.

Social media is a marketing phenomenon that is taking the business world by storm. It goes beyond just being a marketing channel; because it is extremely disruptive by nature and has the potential to affect entire business models. Yet when it comes to social media execution, so many companies get it horribly wrong. Social media remains a part of marketing; it is not a replacement for it. However, it has the ability to redefine many aspects of marketing because it encourages conversation, community involvement and input from the public. Social media is changing the way companies communicate with their target markets. It is opening up new markets and providing channels for companies to not just talk to their customers but to provide new channels of sales to their target market based on trust built up in social media through openness and transparency. Marketing has moved from a push model to model dominated by social media, that of engagement. This study looked at literature that provided information, strategies and frameworks on how to create an effective social media strategy that is executable. The research shows that whilst much literature shares many aspects (the need to listen, engage, set goals, and formulate effective strategies); most of this literature is insufficient in actually providing a sound and effective platform that could be taken to create a strategy from its beginning to the point of execution. This research report creates a new detailed framework and plan that would allow a marketer to take the concept of social media and develop a working strategy and plan, as well as to execute it. It is aimed at marketers and people who have limited social media knowledge, and provides them with what they need to know in order to get started. The framework is a detailed plan that is based on an original social media marketing plan by Brian Solis.

Thesis (MBA)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: History and statistics confirm that social media and the internet has come a long way and is bound to keep evolving and growing in the future. But many opposing views and criticism surround the ubiquitous use thereof. One’s personal social media strategy is the basis of personal branding. Managing the strategy pro-actively and creatively is thus very important. The report gives a quick overview of the web key concepts, technologies and tools currently available for social media participation. These tools are grouped by looking at various current social media classification frameworks that exist. Alas, classification must also somehow make provision for forthcoming platforms – and is thus not conclusive. A discussion of the latest technological, digital and social media trends and adoption factors were also included. Knowledge of the trends influence the personal social media strategy formulation heavily. Intermediaries can also assist to provide the required knowledge or experience and also more extensive services if chosen, because creating content is much different from merely consuming it and the technologies, tools and trends change incredibly fast. Several case studies were analysed to gain insights about guidelines, etiquette, risks, challenges and achievements in the social media arena. The various lessons demonstrated the importance of establishing guidelines for social media participation. The case studies further demonstrated that the level of transparency the world has now, won’t support having different identities for a person. Everybody need to understand and accept the societal shift and adjust their behaviour accordingly, if they want to achieve success in the digital arena. This is also of the essence to CEO’s – as their companies will increasingly require their involvement in the social media arena, in order to remain relevant. All the relevant factors were taken into consideration in order to compile a suggested framework for personal social media strategy compilation. Following the framework, not as a recipe but as a mere guideline, will assist individuals to draw up their own personal social media strategy. The strategy consists of four phases, namely planning, organising, execution and monitoring and are set out with several building blocks contained in each, as well as advice on how to approach each building block. Despite the formality of the given framework, it is imperative to remember to have fun – if the creator is not, the audience certainly also won’t and all the effort will most definitely be wasted. Key words: Personal social media strategy; Social media; Social networking; Social media guidelines; Personal social media strategy framework

Due to an increased flow of refugees over the past few years, affairs of refugees have caught increased attention. The aim of this thesis is to analyze the integration process of an earlier group of quota refugees who came to rural Iceland in 1998, from former Yugoslavia. Eighteen years have passed and the refugees’ views of entering and living in Icelandic society will help to understand the process of integration and the role of migration in an ever-changing social context and in times of rapid globalization. The study aims to explore two questions: 1) How did the life events of the refugees affect their integration processes? 2) How did transnational practices impact the integration processes? In-depth interviews were carried out and a life course perspective was the method used for obtaining the refugees’ stories and life experiences, and to investigate their integration processes. The analysis draws on the theories of integration, life course perspective, transnationalism and social networks. This study indicates that transnational practices are beneficial for the lifetime project of integration. Access to an extended social network of relatives and co-ethnics also plays a crucial role. Another important element for integration is the feeling of normal life, supported by a feeling of security in the physical, economic and institutional sense.