In this chapter I review empirical studies directly testing the

Social media treats all users the same: trusted friend or total stranger, with little or nothing in between. In reality, relationships fall everywhere along this spectrum, a topic social science has investigated for decades under the theme of tie strength. Our work bridges this gap between theory and practice. In this paper, we present a predictive model that maps social media data to tie strength. The model builds on a dataset of over 2,000 social media ties and performs quite well, distinguishing between strong and weak ties with over 85 % accuracy. We complement these quantitative findings with interviews that unpack the relationships we could not predict. The paper concludes by illustrating how modeling tie strength can improve social media design elements, including privacy controls, message routing, friend introductions and information prioritization. Author Keywords Social media, social networks, relationship modeling, ties,

k, community and domesticity have moved from hierarchically arranged, densely knit, bounded groups to social networks. In networked societies: boundaries are more permeable, interactions are with diverse others, linkages switch between multiple networks, and hierarchies are flatter and more recursive. People maneuver through multiple communities, no longer bounded by locality. Organizations form complex networks of alliances and exchanges, often in transient virtual or networked organizations (Bar & Simard, 2001). Workers --especially professionals, technical workers, and managers -- report to multiple peers and superiors. Work relations spill over their nominal work group's boundaries, and may even connect them to outside organizations. In virtual and networked organizations, management by network has people reporting to shifting sets of supervisors, peers, and even nominal subordinates (Wellman, 2001). How people learn is becoming part of this paradigm shift. There has been some mov

Tie-strength has been in the focus of social science research for decades, yet the use of measurement tools or scales has been relatively scarce. The aim of this study was to fill the gap and provide a tool that is able to provide a quantitative and continuous measure of tie strength in social networks. The focus was on virtual communities because the fast expansion of Internet use and the constant growth of on-line communities provide today’s researchers with an excellent opportunity for effective and speedy data collection regarding tie-strength measures in these virtual social groups. The Virtual Tie-Strength Scale (VTS-Scale) consist of 11 questions and it was developed on a sample of 56 people (3080 asymmetric ties) and tested for reliability of smaller sample of 16 (204 asymmetric ties) independent sample participation regularly on a Hungarian discussion board like forum. Reliability coefficients were reassuringly high for both samples, Cronbach alphas of 0.92 and 0.86, respectively. Data triangulation offered evidence for scale validity. In summary, the VTS-Scale and its scoring method seem to provide a valid and reliable measure of tie strength in virtual communities. Although the aim of the research was to develop a tool that measures tie-strength in virtual communities, the tool can be easily modified for off-line social groups. The VTS-Scale is also capable of distinguishing between two components of tie-strength: acquaintances and friendship. However, the content of each component needs further investigation.

this paper, I am indebted to Randall Collins, my discussant at the second annual Penn Economic Sociology Conference, the other conference participants, and to Richard Swedberg, Kiyoteru Tsutsui and Valery Yakubovich. A Theoretical Agenda for Economic Sociology. Mark Granovetter. 6/1/00 2

In trying to manage firms, executives confront emergent "order"---ranging from strong culture to ritualistic bureaucratic structure to informal organization---that may work for or against their intentions, whether aimed at near term cost control or strategic novelties. Compared to extant sociological views of emergent order, complexity science offers an explanation and normative approach that is multidisciplinary in its theory base, with better integration of the various dynamics involved. Prigogine's classic argument is that the 1 laws of thermodynamics would not exist if "order" had not been produced in the first place. However, complexity science---as a general explanation of emergent order---is problematic and inconsistent as its literature has emerged from the physical, biological, and social sciences, thus making its application to the managerial setting problematic. Specifically its handling of reductionist and contextual causal generative mechanisms is hit-and-miss and there is no consistent phrasing, or even attention, what we might think of as the 3 law of thermodymics. My review suggests that: (1) The complexity science "bridge" explanation between quantum entanglement and higher levels of order (atoms and above) is missing as a collective belief among complexity scientists; (2) The classic concept of external (Lorenz) energy-differentials (as control parameters) that cause emergence "at the edge of chaos" is frequently missing; (3) The nature of the entanglement pool or "base"---more broadly the set of network ties among agents such as atoms, molecules, organisms, human actors---from which emergence arises, is often ignored; and (4) Given the possibility in biological and social systems that prior emergence events could have fed back to irrevocably "ta...

Community has traditionally been anchored in local, neighborhood interactions and enshrined as a code word for social cohesion. “Community ” usually connotes people socially and cognitively encapsulated by homogeneous, broadly embracing groups (Hillery, 1955; Wellman, 2001a; Wellman, 2002; Wellman & Leighton, 1979). People in group-based societies deal principally with fellow members of the few groups to which they belong: at home, in school, in the neighborhood, at work or in voluntary organizations. They work in a discrete work group within a single organization; they live in a household in a neighborhood; they are members of one or two kinship groups; and they participate in structured voluntary organizations: churches, bowling leagues, unions, and the like. There have been fears since the Industrial Revolution that traditional group-based community has been “lost”. From the early 1960s, the balance of analysis swung away from bewailing this purported loss of community to using ethnographic and survey techniques to discover the persistence of neighborhood communities. In the 1970s, analysts began realizing

This paper examines the celebrated ‘Strength of weak ties ’ theory of Granovetter (1973). We examine two hypotheses implied by the theory: one, for any three players with two links present, the probability of a third link being present is increasing in the strength of the two ties, and two, the removal of a weak tie breaks more shortest paths than the removal of a strong tie. This paper tests these hypotheses using data on coauthorship among economists. Our data supports the hypothesis of transitivity of strong ties, but it rejects the hypothesis that weak ties are more crucial than strong ties. We then propose an explanation for the strength of strong ties which builds on two properties of the network: one, significant inequality in the distribution of connections across individuals and, two, stronger ties among highly connected individuals.

By em bed d ing subgroups in a sociogram w e generate im ages consistent w ith longstand ing theoretical descriptions of netw ork structure. Moreover, these im ages sustain an eclectic array of theoretically based interp retations, thu s p rovid ing a basis for theoretical integration. W e generate and interpret two images, one of professional discussions among high school teachers and the other of friend ships am ong the French financial elite. Our find ings suggest that this approach has great potential for informing characterizations and interpretations of the structure of various social networks. 1. Theoretical Images of the Structure of Social Networks One of the strongest and most consistent theoretical images of the structure of social networks is that of interactions concentrated within, but not confined to, cohesive subgroups. Such a description was offered early by Roethlisberger and Dickson (1941) who studied workers who organized themselves into cliques within a bank-wiring room, and has been

contained in this dissertation are those of the author and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the