Showing papers in "Social Networks in 1978"

Centrality in social networks conceptual clarification

Abstract: The intuitive background for measures of structural centrality in social networks is reviewed and existing measures are evaluated in terms of their consistency with intuitions and their interpretability. Three distinct intuitive conceptions of centrality are uncovered and existing measures are refined to embody these conceptions. Three measures are developed for each concept, one absolute and one relative measure of the centrality of positions in a network, and one reflecting the degree of centralization of the entire network. The implications of these measures for the experimental study of small groups is examined.

Contacts and influence

Abstract: This essay raises more questions than it answers. In first draft, which we have only moderately revised, it was written about two decades ago and has been circulating in manuscript since then. (References to recent literature have, however, been added.) It was not published previously because we raised so many questions that we did not know how to answer; we hoped to eventually solve the problems and publish. The time has come to cut bait. With the publication of a new journal of human network studies, we offer our initial soundings and unsolved questions to the community of researchers which is now forming in this field. While a great deal of work has been done on some of these questions during the past 20 years, we do not feel that the basic problems have been adequately resolved.

Structural equivalence: Meaning and definition, computation and application

Abstract: This paper presents a generalization of the concept of “structural equivalence”, the key concept in algebraic approaches to the study of social networks. Two points in a graph or set of relations will be called “structurally related” if they are connected in the same ways to structurally related points. It is suggested that this new definition suitably weakens Lorrain and White's categorical approach, and is more appropriate than CONCOR. Structural relatedness is compared to these approaches via several simple examples.

The reversal small-world experiment

Abstract: This paper is an attempt to examine and define the world network of a typical individual by discovering how many of his or her acquaintances could be used as first steps in a small-world procedure, and for what reasons. The town and occupation of each target was provided, together with the ethnic background, where this could not be inferred from the name. Starters were instructed in the small-world experiment and asked to write down their choice, amongst the people they knew, for the first link in a potential chain from them to each of 1267 targets. Starters provided information on each choice made (e.g. mother, cousin, friend, acquaintance, etc.) together with the sex of the choice) and the reason that choice had been made. The reason could be in one or more of four categories: something about the location of the target caused the starter to think of his or her choice; the occupation of the target was responsible for the choice; the ethnicity of the target; or some other, unspecified, reason. Six main conclusions may be drawn from the data: (1) A mean of 210 choices per starter account for the “world” (i.e. the 1267 targets). This number is probably an underestimate. Only 35 choices are necessary to account for half the world, however. Of the 210, 95 (45%) were chosen most often for location reasons, 99 (47%) were chosen most often for occupation reasons, and only 7% of the choices were mainly based on ethnicity or other reasons. (2) Choices were mainly friends and acquaintances, with strong cleavage by sex. For any given target, the type of choice used by the majority of starters was a friend or acquaintance, and not family. For any given target, the most likely sex of the choice (i.e. over all starters) can be predicted accurately on 82% of occasions. This sex tends to be male, unless both starter and target are female, or if the target has a low-status occupation. Additionally, any given starter is most likely to pick a male choice for any target, except for the female starter-female target combination, when female choices are more likely. This was correct on 64% of occasions. (3) Location was the usual reason for choice (out of the four categories), with occupation second, and ethnicity or other reasons rarely used. This most popular reason for choice may be correctly predicted for any given target 81% of the time. (4) The decision as to which choice was made appears to depend primarily on the occupation of the target, and secondly on the distance (near/far) from Morgantown, West Virginia, where the experiment took place. (5) The expression “having one's man in …” can be partially quantified. We may define a choice to “handle” a state in the U.S. if he or she was chosen for two-thirds or more of the targets in that state for which choices were made on the basis of location. Then, for any starter, on average, half the states are each handled by a single choice. (6) The accuracy of starters' recall about their networks is low, in the sense that their recall is incorrect more often than it is correct (i.e. their recall could not be put to any other use with any reliability). This confirms previous experiments on informant accuracy.

The process of friendship formation

Abstract: This paper poses two questions about the process of friendship formation: what is the relative stability of asymmetric and mutual friendship dyads and what is the nature of change in asymmetric dyads over time? These questions are examined in longitudinal sociometric data from five elementary classes. Change in friendship choices is shown to be at least partially embeddable as a continuous time, stationary Markov process and the unique Q matrices governing the process are determined. The findings show that unreciprocated friendship choices of the children in the sample are less stable than reciprocated choices and that their unreciprocated choices tend to be withdrawn rather than reciprocated over time.

Sampling and estimation in large social networks

Abstract: An unknown network is modelled by a directed or undirected graph having vertices of different kinds. Partial information is available concerning the vertex labels and the edge occurrences within a simple random sample of vertices. Using this information we find unbiased estimators and variance estimators of such graph parameters which can be given as dyad or triad counts. In particular, we give approximate formulae pertaining to large networks.

A structural theory of interlocking corporate directorates

Abstract: A theory is proposed that explains where interlocking corporate directorates should appear between sectors of an economy, where they should not appear, and the profitability of efficient corporate interlocking. Taking the sector of an economy as the unit of analysis, interlocking directorates are cast as strategically created constraints on those sectors of the economy most “problematic” for obtaining profits in a given industry of firms. The extent to which each sector of the American economy is problematic for obtaining profits in two-digit and four-digit manufacturing industries is estimated from research linking industry profits with the form of the pattern of relations defining the industry as a position in the network of dollar flow transactions given in the 1967 Input-Output Study for the United States. A two-stage process is described for sampling firms representative of large corporations involved in American manufacturing. Measures of alternative strategies for interlocking across sectors are described. Two classes of hypotheses are derived: (1) Firms in an industry should interlock with firms in some other sector in proportion to the extent to which the sector constrains the industry's profits. (2) Controlling for production and market differences, the ability of firms in an industry to obtain unusually high profits reflects their success in creating interlocks with those sectors most problematic for their industry's profits.

Analysing interlocking directorates: Theory and methods

Abstract: In this review article an overview is given of research on interlocking directorates. The emphasis is on methodological problems and innovations. The start of research on interlocking directorates in Germany and the U.S.A. at the beginning of this century is described. Studies on financial groups are then discussed, followed by the sociological approach and longitudinal studies. Finally, more recent research is discussed, starting with a short introduction to the research on networks of interlocking directorates. In the last section five topics are discussed in more detail: component analysis, groups in the network, different types of interlocking directorates, the stability of interlocking directorates and the relation between different corporate interlocks.

The medieval river trade network of Russia revisited

Abstract: Medieval trade and communication along the rivers of Russia are considered as a social network. Two measures are presented. An intermediate node occurrence rate (Shimbel's stress index) provides a measure of centrality. The short-path distances to all other places are summed to provide a system-effort measure of accessibility. Both measures show Moscow to have been most central and accessible with aggregate least effort.

The rise of network thinking in anthropology

Abstract: The encyclopedic inventory of the first half of the twentieth century, “Anthropology Today”, published in 1953, gave little inkling that within a few decades developing trends in social theory, in field experience, in electronic data processing, and in mathematics would combine to bring to prominence a distinctive theoretical approach using a quite formal network model for social systems. Now, sophisticated mathematics and computer programming permit sophisticated network models — networks seen as sets of links, networks seen as generated structures, and networks seen as flow processes. Although network thinking has shown a dramatic rise from the “Anthropology Today” of 1953 to the current anthropology of 1978, it is predicted to soar in the next quarter century, much of the weighty burden of network analysis having been lifted from us by ever more rapid electronic data processing.

Stratification and prestige among elite experts in methodological and mathematical sociology circa 1975

Abstract: This discussion has two purposes. One is to describe the social differentiation of experts within an elite invisible college devoted to methodological and mathematical work circa 1975. The other is to illustrate the positional approach in network analysis. After introducing the invisible college to be considered, the form of stratification within it is described. Although completely interconnected to one another, experts are stratified across five structurally unique statuses. The form of stratification is given greater empirical meaning by considering its content. There is a subtle linkage between the extent to which a status is defined by substantive and methodological influence relations. The most prominent experts have merged their methodological concerns with specific substantive concerns. The most prestigious status is occupied by a “social statistics elite” to whom a “mobility elite” exists as a satellite status. Methodology leaders among social psychologists divide into a group pursuing the study of three-person groups, a “triads elite”, and a group with more general interests, a “social psychology elite”. Finally, a “mathematical sociology elite” jointly define no status since they have highly dissimilar substantive relations with one another and other experts. The last question addressed concerns the distribution of prestige in the college. As would be expected under a norm of universalism, the relative prestige of experts within the college is uniquely determined only by an expert's record of publishing in the college's core journals. The discussion concludes with comments.

A note on the potential for genuine cross-fertilization between anthropology and mathematics

Abstract: Although there has been much discussion in recent years of the applicability of mathematical methods in the social sciences, little attention has been paid to the interaction of the sociological analysis and the mathematics. In this paper, an example of an extremely fruitful interaction between anthropology and mathematics is described. The interaction has, on the one hand, greatly increased the subtlety and sophistication of the sociological analysis, while on the other hand it has posed interesting mathematical questions.

The determination of enterprise groupings through combined ownership and directorship ties

Abstract: Recent work on economic structure has tended to focus around discovering general or global mappings to represent complex patterns of binary or multiplex ties. By contrast, this paper seeks to define an intermediate level of structure—the “enterprise ”—and to measure it concretely using a combination of ownership and director/officership or executive board membership ties. In the first section, we outline the theoretical and substantive basis of the concept of “enterprises” as it is used in the literature. Difficulties in the operationalization of this concept are then surveyed and some tentative solutions suggested. In the second section, we describe in detail the methods used to implement our definition of enterprises for a set which includes the 5306 firms which most directly shape the Canadian economy. The third section outlines the impact of the use of four slightly different versions of this definition on arrays of enterprise memberships. Finally, the larger implications of our findings—both for the measurement of intermediate levels of structure and for the study of cross-national economic connections—are discussed.

Formal network studies and the anthropological perspective

Abstract: Anthropological social network studies are primarily of interest for an original formulation of the classic sociological problem of reconciling structural and action aspects of social organization. In general, however, these studies have produced disappointing substantive results owing to serious methodological and theoretical difficulties. Within the anthropological tradition are two types of research, viz., structural kinship studies and cognitive anthropological decision models, which have produced sound substantive results and which, if generalized and properly combined, could provide the methodological and theoretical tools which eluded the network scholars.

Corporate-governmental networks in the Netherlands

Abstract: Corporate networks studies have been restricted mainly to the private or business sectors. Network analyses involving both corporations and state or government agencies have been extremely rare. In this paper, the intercorporate network of interlocking directorates in the Netherlands, based on 86 large corporations and financial institutions, is studied in terms of a bipartite corporate—governmental network which arises from the interlocking memberships linking these corporations with major committees, agencies and similar centers of decision in the public sector or central state mechanisms in the Netherlands. The corporations, representing 27 industrial sectors, have been related to government and state agencies in 28 policy sectors. In this exploratory analysis the two heavy industries, metal/shipbuilding and chemicals/oil stand out clearly. With respect to the 17 central firms the results demonstrate consistent correspondence between their central position in the Dutch corporate network and the degree of their interlocks with policy sectors in the state. The results also show that the interlocks are overwhelmingly linked with the two policy sectors “economic affairs” and “education and sciences”. Hence a more detailed analysis of the interlocks with these two policy sectors is reported.

Networks in public policy: Nuclear energy in the Netherlands

Abstract: The article analyses the network of interlocking directorates as a part of public policy analysis of nuclear energy policy in the Netherlands. This network represents an interorganizational communication structure on the policy decision level. An organization's position in this structure reflects its position in policy formulation and implementation. Semi-governmental bodies function as important mediators between central government and private actors, of which the engineering and electricity companies have been the most influential.

Opportunities, information networks and the migration-distance relationship☆

Abstract: The study of the relationship between the volume of migration, on the one hand, and the distance between the migration source and target, on the other, may be traced back at least to the work of E. G. Ravenstein (“The laws of migration” . Journal of the Royal Statistical Society, 48 (1885): 167–227 ; 52 (1889): 241–301), who observed that the vast majority of migrants tend to traverse relatively short distances. Extensive subsequent research has done much to isolate the general mathematical attributes of the migration-distance relationship, yet the causes of this relationship have been relatively ignored and are thus far less well understood. The present research is addressed directly to these underlying causes. In particular, the study evaluates the role of information concerning opportunities and the dispersion of this information in social networks in producing a relationship between migration and distance. Analysis centers on an ethnohistoric migration process, involving the movement of Chumash Indians to the California mission of Santa Barbara .

Opportunities, information networks and international migration streams.

Abstract: Theoretically, the basis for the continuance of international migration streams lies in the free flow of information between origin and destination. The people best informed about possible opportunities at the destination are most likely to emigrate. This idea is expressed as a simple linear equation and tested in predicting the size of migration streams from eight regions in Japan to each of four major Hawaiian Islands. A destination tends to attract new immigrants from an origin in direct proportion to the previously established amount of migration from that origin to that destination. In general, previous migration may have considerable relevance to continuation of streams in the future.