Nowadays people and organizations are more and more interconnected in the forms of social networks: the nodes are social entities and the links are various relationships among them. The social network theory and the methods of social network analysis (SNA) are being increasingly used to study such real-world networks in order to support knowledge management and decision making in organizations. However, most existing social network studies focus on the static topologies of networks. The dynamic network link formation process is largely ignored. This dissertation is devoted to study such dynamic network formation process to support knowledge management and decision making in networked environments. Three challenges remain to be addressed in modeling and analyzing the dynamic network link formation processes. The first challenge is about modeling the network topological changes using longitudinal network data. The second challenge is concerned with examining factors that influence formation of links among individuals in networks. The third challenge is regarding link prediction in evolving social networks. This dissertation presents four essays that address these challenges in various knowledge management domains. The first essay studies the topological changes of a major international terrorist network over a 14-year period. In addition, this paper used a simulation approach to examine this network's vulnerability to random failures, targeted attacks, and real world authorities' counterattacks. The second essay and third essay focuses on examining determinants that significantly influence the link formation processes in social networks. The second essay found that mutual acquaintance and vehicle affiliations facilitate future co-offending link formation in a real-world criminal network. The third essay found that homophily in programming language preference, and mutual are determinants for forming participation links in an online Open Source social network. The fourth essay focuses on the link prediction in evolving social networks. It proposes a novel infrastructure for describing and utilizing the discovered determinants of link formation process (i.e. semantics of social networks) in link prediction to support expert recommendation application in an Open Source developer community. It is found that the integrated mechanism outperforms either user-based or Top-N most recognized mechanism.

Despite the fact that swidden agriculture has been the subject of decades of research, questions remain about the extent to which it is constrained by demographic growth and if it can adapt to environmental limits. In this dissertation I analyze ethnographic and ethnohistorical evidence from the Toledo District, Belize, and suggest that Q'eqchi' Maya swidden agriculture may be more ecologically adaptive than previously thought. I use social network analysis to examine farmer labor exchange networks from a chronosequence of five villages where swidden is used. Results suggest that changes in land-use patterns, network structure, and reciprocity rates may increase the system's resilience to changes in the forest's agricultural productivity. I develop a novel interpretation of labor reciprocity that highlights how unreciprocated exchanges, when they occur within the context of a social network, may limit overexploitation of a common property resource. These results are then interpreted in the context of panarchy theory; I suggest that the structural variability observed in labor exchange networks may explain how Q'eqchi' swidden maintains its identity under changing environmental conditions - a definition of resilience. Thus, the resulting picture of Q'eqchi' swidden is one of socioecological resilience rather than homeostasis; dynamic labor exchange networks help maintain a village's social cohesion, ultimately limiting pioneer settlements and slowing overall rates of deforestation. A historical and demographic analysis of market incursions into southern Belize supports this conclusion.

We study a message passing network where nodes keep a numeric attitude toward a subject. Messages are created by a message factory and each is sent to a random seed-node, which then gets eventually propagated in the network. Each message has some information about the subject, which is interpreted by the receiving node based on its features. Hence, the same message could be interpreted quite differently by two different nodes. Once a message is interpreted, the attitude of the node toward the subject is updated. In this setting, the thesis is that an external agent can influence (in a desired way) the average attitude of the network, by sending the messages to specific nodes (rather than sending them randomly) based on the message content. We call this agent a leader which its goal is to minimize (maximize) the average attitude of the network, and its actions are choosing one of the seed-nodes for a given message. The leader does not have any information about the nodes in advance, instead, it eventually learns the interests of the seed-nodes through sending messages and receiving the feedback of the network. We formulate this as a contextual bandit problem and study the effectiveness of a leader in different network configurations. Moreover, we study the case that there are two adversarial leaders, and present different policies and evaluate their effectiveness. Finally, we study the leader's performance when there are dynamic changes in the nodes features and network's topology.

古今中外歷史中，在政治權力的結構裡，除了在最上位的領袖外，其下的文武百官，往往根據其職份或私交等情況，自成人際關係網絡。然而，依照每個人在網絡中位置的不同，重要程度也有所不同。在網絡中扮演重要角色者，除了代表其人際關係愈複雜外，同時也暗示其政治影響力愈大。這些人物往往也就是足以影響當時政治的「權臣」。然而在歷史上，有些皇帝的在位時間較長、統治時間較久。在其統治期間，可能因為皇帝本身，或政治環境遞嬗等因素，使得不同的時期有不同「權臣」，或是其晚年才出現明顯的「權臣」。本論文便是基於這樣的歷史現象，研究由史料中探勘當時的人脈網絡。我們先從文本中，自動擷取出人名。然後，藉由人物在文本中與其他人物的共現場合，建立歷史人物的人脈網絡，接著利用社會網絡分析的理論基礎，分析這些網絡，進而在網絡中找出權臣，以及偵測政治權力結構的變化，為時代作出分期。本研究選用的文本為《清實錄》中的《高宗純皇帝實錄》，意欲以清高宗 (乾隆)時期為例，探勘該朝的人脈網絡，完成上述之工作。希望這樣的研究，可以在中國政治制度史等研究上，協助史學研究者。 / In power structure from ancient times to the present, officials who under the leader usually take part in the social network according to their positions or friendship. However, the importance of each person is different by their locations in network. The people who play important roles in network have complex interpersonal relationship as well as high influence in political situation. We call them "chief counselors." But in the history, some emperors reign for extremely many years. Due to some causes, such like emperor himself or changing of political circumstances, there could be several different chief counselors during their reign. This thesis focuses on social network mining from historical documents in view of above-mentioned historical phenomenon. After extracting person names from the corpus, we can construct social network by co-occurrence of people, then to find chief counselors and detect transition of power structure by Social Network Analysis. The "Veritable Records of Gaozong" is taken as the example for experiments and the result of effectiveness analysis demonstrates that the proposed methods are helpful to assist historian for historical research.

社會網路分析（social network analysis）將社會關係以網路形式表示，從原本純粹分析社會互動的工具，到近年來被廣泛被應用在社會學、組織研究、資訊科學、生物學、語言學等各種領域，藉由引入數學圖學理論與與日益精進的電腦處理能力，使得社會網路分析能從有別於以往的角度找出個體間行動的規律；而詞義相似度（word similarity）是資訊檢索等技術發展的基礎課題之一，近年來對詞義相似度的量測有許多方法的提出。 本研究針對英語字詞利用社會網路分析這樣的工具，藉由提出不同的網路建構方式，以語料庫為資料來源，設定網路節點與連結關係，以共現網路（co-occurrence networks）為基礎，經由改變產生與篩選的條件，觀察以社會網路分析已有的性質或指標做調整，是否可以對詞義相似度提供另一種量測方式；同時以目前詞義相似度研究上已有同義詞標準評比對前述產生的網路與所計算的性質做驗證，並進一步探討使用社會網路分析在詞義相似度研究上的適用性。

The purpose of the study isto,based on network theory, systems theory and development ecological systems theory,understand parent’sexperiences of having children with autismspectrum, as well as understand the importance of social networksfor the parents. All of the intervieweeswere mothers. The results showed that it is important to parentsto have contact with other parents who are in the same situation as them. Many of the interviewees had a small social network. The parents have tostruggle to get the support they are entitled to and thereforetheyfeel likethe "annoying" parent. Some of the parents felt that they are socially isolated and do not have the energy to maintain asocial life. In some cases,thesurrounding had a lack of patience and understanding for the families with children with autismspectrumand the family did not have the energy to keep in touch with them.The resultsalso showed that all the interviewees have previously had difficulties in the cooperation with the school butithas slowly gotten better, which may be because the mothers have to be the "annoying" parents who require their rights to theirchildren.

Darbo objektas – socialinių tinklų marketingas. Darbo tikslas – išanalizuoti socialinių tinklų marketingo atsiradimą paskatinančius veiksnius, bei atlikti įmonių susijusių su turizmu galimybių socialiniuose tinkluose įvertinimą. Darbo uždaviniai: 1. Atskleisti socialinių tinklų marketingo sampratą. 2. Atlikti socialinių tinklų marketingo galimybių analizę. 3. Išnagrinėti socialinių tinklų marketingo atsiradimą ir veikimo principus. 4. Atskleisti neišnaudotų, socialinių tinklų marketingo, galimybių priežastis įmonių susijusių su turizmu sektoriuje. Hipotezė – socialinių tinklų marketingo galimybės įmonėse turinčiose sąsajas su turizmu, išnaudojamos pilnai ir tinkamai. Atlikus literatūros socialinių tinklų marketingo galimybių literatūrinę analizę išskiriami e - marketingo privalumai, įtakos vartotojui veiksniai, atlikta priežasčių pagal vartotojus ir verslininkus analizė. Išnagrinėjus socialinių tinklų populiarumą paaiškėjo, kad teik pasaulyje, tiek Lietuvoje tarp tokių tinklų lyderiu galime laikyti „Facebook“. Atlikus neišnaudotų galimybių socialiniuose tinkluose tyrimą galima nustatyti ir padaryti tokias išvadas: įmonės neturi pakankamai žinių ir pakankami duomenų analizėms atlikti; įmonės neturi pakankamai kompetentingo personalo; neįvertinamas pilnas marketingo proceso kompleksas; neatitinka vartotojų ir verslininkų požiūriai dėl netinkamos ir neišsamios analizės; netinkamai traktuojamos ir įvertinamos tokio marketingo galimybės. Hipotezė - socialinių tinklų... [toliau žr. visą tekstą] / The object - social network marketing. The aim - to analyze the emergence of social networking marketing incentives, within the factors, and implement enterprise - related tourism opportunities in social networking assessment. The objectives: 1. Reveal social network marketing concept. 2. Perform social network marketing opportunity analysis. 3. Examine the emergence of social network marketing and how it works. 4. Uncover untapped, social network marketing, opportunity, enterprises related to tourism sector. Hypothesis - social network marketing opportunities in companies having links with tourism exploited fully and properly. The literature of social network marketing opportunities for literary analysis distinguishes e - marketing advantages of consumer influence factors , done by reason consumers and business analysis. An examination of the popularity of social networks showed that providers in the world, both in Lithuania between these networks can be considered a leader in Facebook. After untapped social networks to identify and study the following conclusions: the company does not have sufficient knowledge and sufficient data to perform analysis; companies do not have enough qualified personnel; fails to recognize the full marketing process complex; does not meet consumer and business attitudes of inadequate and incomplete analysis; properly treated and evaluated the marketing possibilities. Hypothesis - social network marketing opportunities in companies having links... [to full text]

MySpace is a social network site (SNS) that forms an essential part of modern online communication. The creation of a personal profile in MySpace allows a user to connect with a global network of friends and communicate in a number of different ways. This thesis sets out to explore the experience of MySpace in terms of the self, identity and community. MySpace will be studied from a constructionist form of social psychology that benefits from new dialects of movement, performance and process. MySpace is conceptualised as a mediated community where users shape and are shaped by their experience of using the site. This study uses empirical data taken from the natural use of MySpace. A total of 100 open-access profiles are explored for the myriad ways that users constitute the self and identity in MySpace. The analysis identifies a number of functions of mediating the self including: the brand me, the hoped-for self and the self in potential. The brand me describes the reflective ability to realise other normative capacities through the practice of blogging in MySpace. This focuses on the ability to create new forms of subjectivity in MySpace interactions. In a similar vein, the hoped-for self explains the modification of the self through the act of profile changing and focuses on the actual, everyday practices of the self. Each of these analytic themes demonstrates the importance of the relational connections in MySpace. Finally, the self is defined as in potential as the analysis demonstrates an ongoing need for a narrative construction to the profile that is performed in both the visual and the textual aspects of the page.

Social media such as Facebook, Youtube, Twitter, and online communities plays an important role for knowledge production and diffusion as well as discussions among people. Among social media, online brand communities (OBCs) have recently received attention from both academics and practitioners due to the practical benefits of OBCs for consumers and companies. For consumers, knowledge sharing and its collective activities help them to make purchase decisions and to protect themselves against firms’ monopoly and oligopoly or collusion and anticompetitive actions. For companies, new ideas and feedback on brand products created by OBC members are useful input to develop new products and enhance existing product lines. Therefore, active content generation by community members is one of the critical success factors of OBCs. However, many scholars argue that only a few members who are more devoted to a community are tending to engage in OBC activities and many community members tend to remain in the periphery (sometimes called ‘lurkers') of the community by using OBCs merely for gathering information without any contributions. Therefore, it is important to make members in the periphery of the community transit to the core to increase members’ intentions and ‘devoted members’ to produce more valuable benefits for both consumers and firms. In spite of its importance, the literature is lacking in efforts to explain how and when community members in the periphery transit to the core of the community in a long-term perspective. This study aims to reveal how and why OBC members transit from the periphery to the core of the community and how to increase their intention to use OBC from a long-term perspective. OBC use behaviour is classified into, largely, two categories according to the purposes of an OBC: behaviour with a brand product consumption purpose; and behaviour with a social relationship building purpose. This study classifies OBC members as three clusters by social identity theory: tourists, minglers, and devoted members (devotees and insiders). The devoted members have valuable consumption knowledge of brand and strong social bonds in the OBC and the OBC members become a devoted member by accumulated brand knowledge and experiences through long-term OBC use. Therefore, from a socialisation aspect, this study adopts organisational socialisation theory as the theoretical lens to explain how and why the members evolve from novice members as tourist to devoted members in OBC contexts. Socialisation theories argue that there are usually three sequential stages for a member to gain full membership in a community: pre-entry, accommodation, and affiliation. In addition, this study adopts IS implementation theory to understand OBC user behaviours from an IS use behaviour perspective: acceptance in the pre-entry stage and routinisation in the accommodation stage and infusion in the affiliation stage. By reviewing socialisation theory and IS implementation theory, this study finds four significant motivations, those of information quality, trust, sense of belonging, and brand loyalty for intention of OBC use from the acceptance (pre-entry) to infusion (affiliation) stages. To integrate the socialisation perspective with the IS use perspective, this study adopts a technology acceptance model (TAM) as a theoretical framework to link to motivators in different OBC use behaviour from the acceptance to infusion stages. As a result, this study proposes a conceptual framework to explain the OBC members’ transition process from acceptance (pre-entry) to infusion (affiliation). The aim of this study is to predict and explain the transition of motivators for OBC use from pre-entry to affiliation and how to improve members’ intention of OBC use from a long-term perspective ultimately to foster ‘devoted members’. This study adopts an online survey targeting 518 participants who belong to 17 OBCs in South Korea and the conceptual framework is validated. The results show that all factors (i.e. information quality, trust, sense of belonging, brand loyalty) are significant determinants to increase intention to use OBCs and the factors have a causal relationship with each other to form a transition process from the acceptance (pre-entry) to infusion (affiliation) stages. This study also reveals that brand loyalty has a significant role to explain the transition process and directly influence user intention to use OBCs. The sense of belonging also directly affects members’ intention to use OBCs but has less impact than brand loyalty. In addition, the results indicate that TAM is an appropriate model to predict user behaviours in a long-term perspective to explain the change of OBC use behaviour from the acceptance to infusion stage and confirms that perceived usefulness and perceived ease of use have significant impact on the intention to use OBCs as in other IS studies. Understanding the transition process within OBCs has theoretical and practical implications. Theoretically, it will extend our understanding of how IS end users transit from acceptance behaviour to continued use and extended use of information systems in virtual community contexts. For managers, this study will provide them with insight on how to retain potential consumers in OBCs and facilitate their activities to gain consumer feedback on existing and new products.

This thesis presents a research model to investigate university-students’ acceptance and behaviour in relation to social-networking sites (SNS). In order to carry out this investigation, the research project was divided into two phases using qualitative and quantitative data based on a diverse sample of university students. Phase One used a think-aloud technique to explore the interaction experiences associated with students’ use of Facebook, a popular social-networking site. Twenty-six participants from Teesside University took part in the first study and six categories of experience (communication, gratification, inquisitiveness, evocation, interconnection, apprehension, and ambience) were identified. Subsequently conceptual similarities were found between all six categories of experience and six psychological human needs (relatedness, pleasure, popularity, security, competence and meaning). In Phase Two, a research model was constructed, based on existing literature on technology acceptance and the psychological needs identified in Phase One. Results from an online survey of 766 university students in the United Kingdom, who were also SNS users, provided evidence for the proposed model. The model explained and predicted students’ adoption of SNS, accounting for half of the variance in behavioural intention and almost a quarter of the variance in actual use behaviour. The results showed that students’ personal beliefs, social identity and psychological human needs influenced their decision to adopt SNS. Specifically, user-perceived usefulness, ease of use, enjoyment and credibility were found to iv be important factors in students’ adoption of SNS. The influence of social identity on students’ behavioural intention was also found to be mediated by perceived usefulness and perceived ease of use. Furthermore, the findings emphasise the importance of psychological human needs in students’ adoption of SNS. In particular, the need for relatedness was found to be a significant independent predictor of behavioural intention. Based on the results of this study, theoretical and practical implications are discussed.