Annual Review of Sociology

Similarity breeds connection. This principle—the homophily principle—structures network ties of every type, including marriage, friendship, work, advice, support, information transfer, exchange, comembership, and other types of relationship. The result is that people's personal networks are homogeneous with regard to many sociodemographic, behavioral, and intrapersonal characteristics. Homophily limits people's social worlds in a way that has powerful implications for the information they receive, the attitudes they form, and the interactions they experience. Homophily in race and ethnicity creates the strongest divides in our personal environments, with age, religion, education, occupation, and gender following in roughly that order. Geographic propinquity, families, organizations, and isomorphic positions in social systems all create contexts in which homophilous relations form. Ties between nonsimilar individuals also dissolve at a higher rate, which sets the stage for the formation of niches (localized positions) within social space. We argue for more research on: (a) the basic ecological processes that link organizations, associations, cultural communities, social movements, and many other social forms; (b) the impact of multiplex ties on the patterns of homophily; and (c) the dynamics of network change over time through which networks and other social entities co-evolve.

Social science research on stigma has grown dramatically over the past two decades, particularly in social psychology, where researchers have elucidated the ways in which people construct cognitive categories and link those categories to stereotyped beliefs. In the midst of this growth, the stigma concept has been criticized as being too vaguely defined and individually focused. In response to these criticisms, we define stigma as the co-occurrence of its components–labeling, stereotyping, separation, status loss, and discrimination–and further indicate that for stigmatization to occur, power must be exercised. The stigma concept we construct has implications for understanding several core issues in stigma research, ranging from the definition of the concept to the reasons stigma sometimes represents a very persistent predicament in the lives of persons affected by it. Finally, because there are so many stigmatized circumstances and because stigmatizing processes can affect multiple domains of people's lives, stigmatization probably has a dramatic bearing on the distribution of life chances in such areas as earnings, housing, criminal involvement, health, and life itself. It follows that social scientists who are interested in understanding the distribution of such life chances should also be interested in stigma.

This paper reviews the literature on organizational learning. Organizational learning is viewed as routine-based, history-dependent, and target-oriented. Organizations are seen as learning by encoding inferences from history into routines that guide behavior. Within this perspective on organizational learning, topics covered include how organizations learn from direct experience, how organizations learn from the experience of others, and how organizations develop conceptual frameworks or paradigms for interpreting that experience. The section on organizational memory discusses how organizations encode, store, and retrieve the lessons of history despite the turnover of personnel and the passage of time. Organizational learning is further complicated by the ecological structure of the simultaneously adapting behavior of other organizations, and by an endogenously changing environment. The final section discusses the limitations as well as the possibilities of organizational learning as a form of intelligence.

▪ Abstract  This paper assesses and synthesizes the cumulative results of a new “neighborhood-effects” literature that examines social processes related to problem behaviors and health-related outcomes. Our review identified over 40 relevant studies published in peer-reviewed journals from the mid-1990s to 2001, the take-off point for an increasing level of interest in neighborhood effects. Moving beyond traditional characteristics such as concentrated poverty, we evaluate the salience of social-interactional and institutional mechanisms hypothesized to account for neighborhood-level variations in a variety of phenomena (e.g., delinquency, violence, depression, high-risk behavior), especially among adolescents. We highlight neighborhood ties, social control, mutual trust, institutional resources, disorder, and routine activity patterns. We also discuss a set of thorny methodological problems that plague the study of neighborhood effects, with special attention to selection bias. We conclude with promising strategies and directions for future research, including experimental designs, taking spatial and temporal dynamics seriously, systematic observational approaches, and benchmark data on neighborhood social processes.

Data on social networks may be gathered for all ties linking elements of a closed population (“complete” network data) or for the sets of ties surrounding sampled individual units (“egocentric” network data). Network data have been obtained via surveys and questionnaires, archives, observation, diaries, electronic traces, and experiments. Most methodological research on data quality concerns surveys and questionnaires. The question of the accuracy with which informants can provide data on their network ties is nontrivial, but survey methods can make some claim to reliability. Unresolved issues include whether to measure perceived social ties or actual exchanges, how to treat temporal elements in the definition of relationships, and whether to seek accurate descriptions or reliable indicators. Continued research on data quality is needed; beyond improved samples and further investigation of the informant accuracy/reliability issue, this should cover common indices of network structure, address the consequences of sampling portions of a network, and examine the robustness of indicators of network structure and position to both random and nonrandom errors of measurement.

Over the past decade, focus groups and group interviews have reemerged as a popular technique for gathering qualitative data, both among sociologists and across a wide range of academic and applied research areas. Focus groups are currently used as both a self-contained method and in combination with surveys and other research methods, most notably individual, in-depth interviews. Comparisons between focus groups and both surveys and individual interviews help to show the specific advantages and disadvantages of group interviews, concentrating on the role of the group in producing interaction and the role of the moderator in guiding this interaction. The advantages of focus groups can be maximized through careful attention to research design issues at both the project and the group level. Important future directions include: the development of standards for reporting focus group research, more methodological research on focus groups, more attention to data analysis issues, and more engagement with the concerns of the research participants.

The inverse relationships between socioeconomic status (SES) and unhealthy behaviors such as tobacco use, physical inactivity, and poor nutrition have been well demonstrated empirically but encompass diverse underlying causal mechanisms. These mechanisms have special theoretical importance because disparities in health behaviors, unlike disparities in many other components of health, involve something more than the ability to use income to purchase good health. Based on a review of broad literatures in sociology, economics, and public health, we classify explanations of higher smoking, lower exercise, poorer diet, and excess weight among low-SES persons into nine broad groups that specify related but conceptually distinct mechanisms. The lack of clear support for any one explanation suggests that the literature on SES disparities in health and health behaviors can do more to design studies that better test for the importance of the varied mechanisms.

People are interconnected, and so their health is interconnected. In recognition of this social fact, there has been growing conceptual and empirical attention over the past decade to the impact of social networks on health. This article reviews prominent findings from this literature. After drawing a distinction between social network studies and social support studies, we explore current research on dyadic and supradyadic network influences on health, highlighting findings from both egocentric and sociocentric analyses. We then discuss the policy implications of this body of work, as well as future research directions. We conclude that the existence of social networks means that people's health is interdependent and that health and health care can transcend the individual in ways that patients, doctors, policy makers, and researchers should care about.

▪ Abstract  Sociologists often model social processes as interactions among variables. We review an alternative approach that models social life as interactions among adaptive agents who influence one another in response to the influence they receive. These agent-based models (ABMs) show how simple and predictable local interactions can generate familiar but enigmatic global patterns, such as the diffusion of information, emergence of norms, coordination of conventions, or participation in collective action. Emergent social patterns can also appear unexpectedly and then just as dramatically transform or disappear, as happens in revolutions, market crashes, fads, and feeding frenzies. ABMs provide theoretical leverage where the global patterns of interest are more than the aggregation of individual attributes, but at the same time, the emergent pattern cannot be understood without a bottom up dynamical model of the microfoundations at the relational level. We begin with a brief historical sketch of the shift from “factors” to “actors” in computational sociology that shows how agent-based modeling differs fundamentally from earlier sociological uses of computer simulation. We then review recent contributions focused on the emergence of social structure and social order out of local interaction. Although sociology has lagged behind other social sciences in appreciating this new methodology, a distinctive sociological contribution is evident in the papers we review. First, theoretical interest focuses on dynamic social networks that shape and are shaped by agent interaction. Second, ABMs are used to perform virtual experiments that test macrosociological theories by manipulating structural factors like network topology, social stratification, or spatial mobility. We conclude our review with a series of recommendations for realizing the rich sociological potential of this approach.

I review the development of the political opportunity or political process perspective, which has animated a great deal of research on social movements. The essential insight—that the context in which a movement emerges influences its development and potential impact—provides a fruitful analytic orientation for addressing numerous questions about social movements. Reviewing the development of the literature, however, I note that conceptualizations of political opportunity vary greatly, and scholars disagree on basic theories of how political opportunities affect movements. The relatively small number of studies testing political opportunity hypotheses against other explanations have generated mixed results, owing in part to the articulation of the theory and the specifications of variables employed. I examine conflicting specifications of the theory by considering the range of outcomes scholars address. By disaggregating outcomes and actors, I argue, we can reconcile some of the apparent contradictions and build a more comprehensive and robust theory of opportunities and social movements.