This study investigated the factors that influence foreign language instructors to adopt the use of educational technology as a supplement to their on-campus face-to-face classes. In particular, this study explored the various educational technologies that the foreign language instructors in one public post-secondary institution used to meet their teaching and learning objectives and the factors that affected their technology selection decisions. Previous literature has shown that the field of language education has historically included educational technology but few studies have explored the role that conversations amongst instructors can have on their technology adoption decisions. This study, therefore, utilized social network theory to explore the effects of foreign language instructors’ conversations with one another on their technology adoption decisions. The findings revealed an emerging trend for instructors who had adopted a greater number of technologies to be in a central position in their departmental social network influencing the spread of information and subsequently helping promote technology to their peers. However, interview data concluded that the most influential factors for technology adoption are not the result of these social networks or conversations, but are consistent with Davis’ Technology Acceptance Model instead. / 2012-10

An increasing number of models have been proposed to explain the link structure observed in complex networks. The central problem addressed in this thesis is: how do we select the best model? The model-selection method we implement is based on supervised learning. We train a classifier on six complex network models incorporating various link attachment mechanisms, including preferential attachment, copying and spatial. For the classification we represent graphs as feature vectors, integrating common complex network statistics with raw counts of small connected subgraphs commonly referred to as graphlets. The outcome of each experiment strongly indicates that models which incorporate the preferential attachment mechanism fit the network structure of Facebook the best. The experiments also suggest that graphlet structure is better at distinguishing different network models than more traditional complex network statistics. To further the understanding of our experimental results, we compute the expected number of triangles, 3-paths and 4-cycles which appear in our selected models. This analysis shows that the spatial preferential attachment model generates 3-paths, triangles and 4-cycles in abundance, giving a closer match to the observed network structure of the Facebook networks used in our model selection experiment. The other models generate some of these subgraphs in abundance but not all three at once. In general, we show that our selected models generate vastly different amounts of triangles, 3-paths and 4-cycles, verifying our experimental conclusion that graphlets are distinguishing features of these complex network models.

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Note: / The present research examined incidents of social stress in the lives of young adults. The goal was to determine the role that friendships might play when young adults engage in social support and conflict resolution to deal with such stress. Three studies examined young adults' friendships in terms of how they fulfill various functions or provide interpersonal resources. Study 1 established that social stressors were common, that a variety of stressful transactions with peers were upsetting to young adults, and that young adults tended to use more approach than avoidance coping. Effective coping in response to social stress was related to perceptions of support from a friend, particularly if young adults felt that their friend was an enjoyable companion and was reliable.[...] / La présente étude examinait la fréquence de stress social dans la vie de jeunes adultes. Le but était de déterminer le rôle que peut jouer l'amitié lorsque de jeunes adultes sont en situation de soutien social ou de résolution de conflits pour faire face a ces stress. Trois études examinent comment les amitiés de jeunes adultes remplissent différentes fonctions ou apportent du soutien interpersonnel. Étude 1 établie la fréquence de stress social, que plusieurs transactions stressantes avec leurs paires étaient bouleversantes pour les jeunes adultes, et que les jeunes adultes avaient plutôt tendances a utiliser des techniques d'approche que d'évitement afin de résoudre ces stress. L'utilité de stratégies de négociation efficaces étaient associées a la perception de soutien d'une amie, surtout si les jeunes adultes croyaient que leur amie était une campagne plaisante et fiable.[...]

Written as three publishable papers, this dissertation examines the sources of several forms of social capital in Singapore, and the effects of social capital on occupational success. Using representative survey data from Singapore, these papers make several important theoretical contributions: The first paper examines how and why categorical forms of stratification such as gender and ethnicity tend to produce distinctive forms of network inequalities: for example, whereas Chinese (relative to Malays and Indians) tend to have greater access to well-educated, wealthy, Chinese and weak tie social capital (but not non-kin), men (relative to women) tend to have greater access to men, non-kin and weak ties (but not well-educated, wealthy and Chinese). The key to understanding such distinctive patterns of network inequalities (by gender and ethnicity) is to understand the distinctive ways in which gender and ethnic groups are distributed in routine organizations such as schools, paid work and voluntary associations. The second paper examines the significance of personal contacts in job searches, in the context of Singapore’s meritocratic system. I show that in certain sectors such as the state bureaucracy, social networking brings no distinct advantages as appointments are made exclusively on the basis of the credentials of the candidates. Thus, personal contacts are not always useful, especially in labour markets that rely heavily on the signalling role of academic credentials to match people to jobs. In contrast, personal contacts are more useful among less qualified job searches in the private sector. The third paper shows that while job contacts (i.e. ‘mobilized’ social capital) may not always pay off in meritocratic labour markets, ‘accessed’ social capital remains extremely important. The leveraging power of social capital in meritocratic markets is not the active mobilization of job contacts per se, but more subtly, the result of embedded social resources such as knowing many university graduates and wealthy people. Together, these papers illustrate how socio-structural factors such as meritocracy, gender and racialization form important predictors of the distribution, role and value of social capital in everyday life and labour markets.

Written as three publishable papers, this dissertation examines the sources of several forms of social capital in Singapore, and the effects of social capital on occupational success. Using representative survey data from Singapore, these papers make several important theoretical contributions: The first paper examines how and why categorical forms of stratification such as gender and ethnicity tend to produce distinctive forms of network inequalities: for example, whereas Chinese (relative to Malays and Indians) tend to have greater access to well-educated, wealthy, Chinese and weak tie social capital (but not non-kin), men (relative to women) tend to have greater access to men, non-kin and weak ties (but not well-educated, wealthy and Chinese). The key to understanding such distinctive patterns of network inequalities (by gender and ethnicity) is to understand the distinctive ways in which gender and ethnic groups are distributed in routine organizations such as schools, paid work and voluntary associations. The second paper examines the significance of personal contacts in job searches, in the context of Singapore’s meritocratic system. I show that in certain sectors such as the state bureaucracy, social networking brings no distinct advantages as appointments are made exclusively on the basis of the credentials of the candidates. Thus, personal contacts are not always useful, especially in labour markets that rely heavily on the signalling role of academic credentials to match people to jobs. In contrast, personal contacts are more useful among less qualified job searches in the private sector. The third paper shows that while job contacts (i.e. ‘mobilized’ social capital) may not always pay off in meritocratic labour markets, ‘accessed’ social capital remains extremely important. The leveraging power of social capital in meritocratic markets is not the active mobilization of job contacts per se, but more subtly, the result of embedded social resources such as knowing many university graduates and wealthy people. Together, these papers illustrate how socio-structural factors such as meritocracy, gender and racialization form important predictors of the distribution, role and value of social capital in everyday life and labour markets.

The objective of this study was to elucidate the possible importance of factors from the social environment for the development of depression. As a theoretical framework, Engel's biopsychosocial model (Engel, 1980), based on systems theory, has been applied. Proceeding from the single individual (characterized by experience, personality, behaviour) as the highest level of the organismic hierarchy the following system levels have been taken into account: dyads, family, community, culture-subculture. The depressive patients (n=lll) showed to be living in a narrowed social network and to lack confiding relationships compared with a non-psychiatric control sample (n=98). The personality characteristics (e.g. anxiety, detachment, suspicion) of the patients were related to experienced loneliness, contact difficulties, social network features and leisure activities. By means of a discriminant analysis 83% of the subjects could be correctly classified. In a study of perceived parental rearing, depressives showed to have experienced lack of emotional warmth. As regards social class an overrepresentation of social class III in the subgroups of unipolar, bipolar and unspecified depression was observed. Finally, implications for treatment are discussed in favour of a combination of drug and cognitive psychotherapy. Future research strategies are also suggested. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1985, härtill 8 uppsatser.</p> / digitalisering@umu

In this dissertation I first develop a theoretical framework that explores different components of dynamic capabilities related to firm’s boundary-spanning linkages across two different types of inter-organizational activities - alliances and networks. I argue that there are four different subsets of dynamic capabilities simultaneously at work: alliance opportunity-sensing, alliance opportunity-seizing, network opportunity-sensing and network opportunity-seizing. Furthermore, I argue that there are significant interaction effects between these distinctive subsets driving the firm’s overall effectiveness in sensing and seizing of novel and innovative external opportunities. In order to explore potential interdependencies and draw distinctions among different dynamic capability subsets I integrate concepts from the two theoretical perspectives that often neglect the emphasis of the other - the dynamic capability view and the social network perspective. I then test the hypothesized relationships in the context of firms actively patenting in nanotechnology. Nanotechnology innovations are multidisciplinary in nature and require search and discovery across multiple inter-organizational, scientific, geographic, industry, or technological domains by a particular firm. The findings offer support for the conceptualizations of dynamic capabilities as consisting of distinct subsets of capabilities for the sensing and the seizing of external new-knowledge opportunities. The findings suggest that firm’s innovativeness in an interdisciplinary scientific field such as nanotechnology is the function of the vector of multi-dimensional dynamic capabilities that are context-specific. Furthermore, the findings also suggest that there are inherent trade-offs embedded in different dimensions of dynamic capabilities when deployed across a wide range of inter-organizational relationships.

<p>Serving more than one billion users around the world, today's online </p><p>social networks (OSNs) pervade our everyday life and change the way people </p><p>connect and communicate with each other. However, the open nature of </p><p>OSNs attracts a constant interest in attacking and exploiting them. </p><p>In particular, they are vulnerable to various attacks launched through </p><p>malicious accounts, including fake accounts and compromised real user </p><p>accounts. In those attacks, malicious accounts are used to send out </p><p>spam, spread malware, distort online voting, etc.</p><p>In this dissertation, we present practical systems that we have designed </p><p>and built to help OSNs effectively throttle malicious accounts. The overarching </p><p>contribution of this dissertation is the approaches that leverage the fundamental </p><p>weaknesses of attackers to defeat them. We have explored defense schemes along </p><p>two dimensions of an attacker's weaknesses: limited social relationships </p><p>and strict economic constraints.</p><p>The first part of this dissertation focuses on how to leverage social </p><p>relationship constraints to detect fake accounts. We present SybilRank, a novel </p><p>social-graph-based detection scheme that can scale up to OSNs with billions of </p><p>users. SybilRank is based on the observation that the social connections between </p><p>fake accounts and real users, called attack edges, are limited. It formulates </p><p>the detection as scalable user ranking according to the landing probability of </p><p>early-terminated random walks on the social graph. SybilRank generates an informative </p><p>user-ranked list with a substantial fraction of fake accounts at the bottom, </p><p>and bounds the number of fake accounts that are ranked higher than legitimate </p><p>users to O(log n) per attack edge, where n is the total number of users. We have </p><p>demonstrated the scalability of SybilRank via a prototype on Hadoop MapReduce, </p><p>and its effectiveness in the real world through a live deployment at Tuenti, </p><p>the largest OSN in Spain.</p><p>The second part of this dissertation focuses on how to exploit an attacker's </p><p>economic constraints to uncover malicious accounts. We present SynchroTrap, a system </p><p>that uncovers large groups of active malicious accounts, including both fake </p><p>accounts and compromised accounts, by detecting their loosely synchronized actions.</p><p>The design of SynchroTrap is based on the observation that malicious accounts usually </p><p>perform loosely synchronized actions to accomplish an attack mission, due to </p><p>limited budgets, specific mission goals, etc. SynchroTrap transforms the detection </p><p>into a scalable clustering algorithm. It uncovers large groups of accounts </p><p>that act similarly at around the same time for a sustained period of time. To </p><p>handle the enormous volume of user action data in large OSNs, we designed SynchroTrap</p><p>as an incremental processing system that processes small data chunks on a daily </p><p>basis but aggregates the computational results over the continuous data stream. </p><p>We implemented SynchroTrap on Hadoop and Giraph, and we deployed it on Facebook </p><p>and Instagram. This deployment has resulted in the unveiling of millions of malicious </p><p>accounts and thousands of large attack campaigns per month.</p> / Dissertation