How much of a network does the GSS and RSW dredge up?

Personal network researchers have extensively studied the characteristics and effects of individuals’ closest relationships, but they have paid much less attention to broader acquaintanceship networks, despite evidence that weak ties can also provide social support. In this paper we focus on one aspect of these networks: acquaintanceship volume. We estimate its distributional parameters for a large, representative sample of the general population of Spain, explore its variation across social groups as well as its implications for social support availability. We designed a survey instrument based on the Network Scale-Up Method and implemented it in a national survey in Spain. Our results suggest that Spaniards have approximately 536 acquaintances, with a large inter-individual variation, comparable to the estimates reported for the American population. Acquaintanceship volume varies with gender, age, education, and income. These differences are partially related to the unequal participation of social groups in voluntary associations, confirming the civic value of such associations, and in employment. Even with similar core network size, acquaintanceship volume increases the likelihood of having adequate social support available, suggesting that broader acquaintanceship networks also structure individual outcomes.

Since the 1970s sociologists have explored the best means for measuring social networks, although few name generator analyses have used sociocentric data or data from developing countries, partly because sociocentric studies in developing countries have been scant. Here, we analyze 12 different name generators used in a sociocentric network study conducted in 75 villages in rural Karnataka, India. Having unusual sociocentric data from a non-Western context allowed us to extend previous name generator research through the unique analyses of network structural measures, an extensive consideration of homophily, and investigation of status difference between egos and alters. We found that domestic interaction questions generated networks that were highly clustered and highly centralized. Similarity between respondents and their nominated contacts was strongest for gender, caste, and religion. We also found that domestic interaction name generators yielded the most homogeneous ties, while advice questions yielded the most heterogeneous. Participants were generally more likely to nominate those of higher social status, although certain questions, such as who participants talk to uncovered more egalitarian relationships, while other name generators elicited the names of social contacts distinctly higher or lower in status than the respondent. Some questions also seemed to uncover networks that were specific to the cultural context, suggesting that network researchers should balance local relevance with global generalizability when choosing name generators.

Disagreement surrounds a formal definition of ‘critical mass’ and of the economic willingness to pay for membership in a social network. Our paper adapts work from percolation theory to analyze the structure of social networks, and draws an analogy for critical mass in social networks to the concept of phase changes in materials. We show how network growth can be actively managed, and define how to manage the willingness to pay for membership. We show, if achieving a critical mass of members in a social network is our objective, that prior to achieving critical mass, (1) the probability of accepting an invitation must vary inversely with individuals’ breadth of contacts; and (2) the number of special interest groups of any size will decrease following a power law until immediately below critical mass. Targeted invitations enabled through sophisticated programs such as AdWords and IndexTools can help to actively maximize the probability of forming an acquaintance link. Our model defines a willingness to pay for network membership that is nearly zero below critical mass, and is an involved function above critical mass whose shape appears to be close to a logarithmic function. Our robust measure of the connectedness of members of a particular social network yields values that are consistent with the independently developed metrics of Odlyzko and Tilly [Odlyzko, A., and Tilly, B. A refutation of Metcalfe’s Law and a better estimate for the value of networks and network interconnections, 2005 (downloaded from http://www.dtc.umn.edu/~odlyzko July 3, 2008)], and differ from eponymous ‘laws’ of Sarnoff, Metcalfe and Reed. There also appears to be plausible evidence in support of the market actually pricing networks at values close to Odlyzko and Tilly’s estimates.

This paper investigates the relationship between self-employment and social networks in urban China, an economy rife with informational and institutional imperfections, under-developed financial markets, but a growing and important non-state sector. Having a social network can help the self-employed access supply and credit networks, and assist in navigating an uncertain institutional environment where permissions and licenses often require inter-personal relationships to facilitate and reduce the informational costs of enforcement by dealing with known persons. Thus, holding other productive and observable traits constant including attitude toward risk where possible, social networks are expected to be a significant correlate to self-employment which is borne out by the evidence. Examining three tranches of the self-employed (those who are self-employed, those who are self-employed as a second job, and a sub-sample who have experienced unemployment and then became self-employed), the paper finds that social networks significantly predict self-employment except for those who are working for themselves as a second job. Gender differences are also notable.

Collecting survey data on ego-centered social networks is a difficult task, owing to the complex questionnaire format. Usually, the interviewer handles the dynamics of the question–answer exchange, motivates the respondent and ensures the proper recording of the data. Self-administered modes of data collection, especially web data collection, are more problematic, as the respondents are left alone with a complex and burdensome questionnaire. Therefore, questionnaire layout is crucial for ensuring cooperation and data quality. In this paper we examined three key components of the corresponding web questionnaire: the number of name boxes using a single name generator, question format for assessing alter characteristics (i.e. alter-wise vs. question-wise) and number of name interpreters (i.e. alter characteristics). The number of name boxes was found to be essential for the reported size of social networks and also for some aspects of data quality. Specific data quality effects were also found with respect to variations in question format, where question-wise format performed better than alter-wise. The number of name interpreters had a relatively minor effect. Suggestions for possible standardization of the web interface layout are also given, so that equivalence with other data collection modes can be established.

This article uses data on ‘network instability’ to show how differences across multiple measurements on the membership of personal networks can yield important insights into the nature of these networks. The data come from a sample of 234 recent widows, aged 59–85, who completed seven interviews about their networks over a 1-year period. We use these data to investigate the stability of both overall networks and individual ties, as well as the linkage between the stability of individual ties and the stability of the network's aggregate properties. We find that instability in these networks is best thought of in terms of an underlying ‘core-periphery’ structure, whereby some network members are likely to be named repeatedly (the core), while others are relatively unlikely to appear in any given elicitation of the network (the periphery). We explore the implications of this core-periphery structure for cross-sectional elicitations of personal networks.