A Lomi
Biographic Data
| ID | 15546 |
|---|---|
| NAME | A Lomi |
| GIVEN NAMES | A |
| FAMILY NAME | Lomi |
| SIGNATURE | LOMI A |
| AFFILIATIONS | Università della Svizzera italiana |
| ORCID | 0000-0002-2858-0022 |
| VERIFIED | Yes |
| TOTAL WORKS | 33 |
| TOTAL CITATIONS | 135 |
| AUTHOR COUNT | 32 |
| EDITOR COUNT | 1 |
| FIRST PUBLICATION YEAR | 1995 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 7 |
Gender differences in workplace friendship development
Duality
Culture as configurations of categories
The dual clustering of tastes and ties
Sociological research on culture has long conceptualized categorical differentiation in terms of relational “distances” and relied on network imagery to describe the structural properties of fields of cultural production and consumption. Partly constrained by research design, extant research on relational similarity often focuses on either one-mode social networks, or two-mode cultural affiliation networks independently. Only a few recent empiric…
A time to give and a time to receive
Relational event models in network science
Relational event models (REMs) for the analysis of social interaction were first introduced 15 years ago. Since then, a number of important substantive and methodological contributions have produced their progressive refinement and hence facilitated their increased adoption in studies of social and other networks. Today REMs represent a well-established class of statistical models for relational processes. This special issue of Network Science de…
A network centrality bias
Combining the results of two empirical studies, we investigate the role of alters' motivation in explaining change in ego's network position over time. People high in communal motives, who are prone to supportive and altruistic behavior in their interactions with others as a way to gain social acceptance, prefer to establish ties with co-workers occupying central positions in organizational social networks. This effect results in a systematic net…
Multiple clocks in network evolution
Relational event models shift the analytical focus away from network ties defined in terms of transitions between mutually exclusive states of connectivity, to bonding processes emerging from observable flows linking senders and receivers of action. In this framework, the possibility to connect social mechanisms of theoretical interest to sequences of observed relational events depends on the relative speed at which these mechanisms operate. Buil…
Lost in translation
Some of the constitutive features of social relations are lost when information naturally produced by sequential social interaction is translated into network ties. Building on core concepts and ideas developed within conversation analysis, in this paper we argue that this happens because the sequential, multimodal and embodied character of social relations can be fully understood only with reference to the sequential constrains that are generate…
Dynamic network analysis of contact diaries
Analyzing two-mode networks linking actors to events they attend may help to uncover the structure and evolution of social networks. This classic social network insight is particularly valuable in the analysis of data extracted from contact diaries where contact events produce — and at the same time are the product of relations among participants. Contact events may comprise any number of actors meeting at a specific point in time. In this paper …
Beyond homophily
We consider the specification of effects of numerical actor attributes, having an interval level of measurement, in statistical models for directed social networks. A fundamental mechanism is homophily or assortativity, where actors have a higher likelihood to be tied with others having similar values of the variable under study. But there are other mechanisms that may also play a role in how the attribute values of two actors influence the likel…
Reliability of relational event model estimates under sampling
We assess the reliability of relational event model (REM) parameters estimated under two sampling schemes: (1) uniform sampling from the observed events and (2) case–control sampling which samples nonevents, or null dyads (“controls”), from a suitably defined risk set. We experimentally determine the variability of estimated parameters as a function of the number of sampled events and controls per event, respectively. Results suggest that REMs ca…
Team diversity, polarization, and productivity in online peer production
The free encyclopedia that anyone can dispute
Some days are better than others
The Network Dynamics of Status
Using longitudinal data that we have collected on friendship and advice relations in a cohort of MBA students, we examine how status affects the dynamics of network ties among peers. Estimates of Stochastic Actor-Oriented Models (SAOMs) suggest that status is a consequence of network ties because over time the level of status attributed to individual students by other students tends to the average level of status attributed to their network partn…
Multilevel social spaces
In this paper, we seek to advance an updated concept of social space that integrates the multilayer and dynamic statistical network methods currently at the disposal of social network researchers. We demonstrate the analytic value of the new concept of social space that we propose with the help of an illustrative analysis of an organizational field involving organizations' external and internal decisions that congeal into a multilevel system of a…
Investigating the Temporal Dynamics of Interorganizational Exchange
Previous research on interaction behavior among organizations (resource exchange, collaboration, communication) has typically aggregated those behaviors over time as a network of organizational relationships. The authors instead study structural-temporal patterns in organizational exchange, focusing on the dynamics of reciprocation. Applying this lens to a community of Italian hospitals during 2003–7, the authors observe two mechanisms of interor…
The embeddedness of organizational performance
Assimilation and differentiation
Introduction to multilevel social networks
Computer Simulation
Computer simulation is a distinctive approach to the representation of organizational theories. In this article I discuss some of the premises and promises of computer simulation as an approach to studying organizations.
Simultaneous modeling of initial conditions and time heterogeneity in dynamic networks
In dynamic networks, the presence of ties are subject both to endogenous network dependencies and spatial dependencies. Current statistical models for change over time are typically defined relative to some initial condition, thus skirting the issue of where the first network came from. Additionally, while these longitudinal network models may explain the dynamics of change in the network over time, they do not explain the change in those dynamic…
The Network Dynamics of Social Status
The distinction between network theories and theories of networks is particularly salient in studying social status because social status is both a consequence and an antecedent of network ties. Status is a consequence of network ties because it is conferred by interdependent acts of deference connecting a sender and a recipient. Status is also an antecedent of network ties because it affects individual preferences for social interaction which pr…
Social Networks and Social Settings
Why are some more peer than others? Evidence from a longitudinal study of social networks and individual academic performance
Beyond homophily
We consider the specification of effects of numerical actor attributes, having an interval level of measurement, in statistical models for directed social networks. A fundamental mechanism is homophily or assortativity, where actors have a higher likelihood to be tied with others having similar values of the variable under study. But there are other mechanisms that may also play a role in how the attribute values of two actors influence the likel…
Some days are better than others
Investigating the Temporal Dynamics of Interorganizational Exchange
Previous research on interaction behavior among organizations (resource exchange, collaboration, communication) has typically aggregated those behaviors over time as a network of organizational relationships. The authors instead study structural-temporal patterns in organizational exchange, focusing on the dynamics of reciprocation. Applying this lens to a community of Italian hospitals during 2003–7, the authors observe two mechanisms of interor…
Simultaneous modeling of initial conditions and time heterogeneity in dynamic networks
In dynamic networks, the presence of ties are subject both to endogenous network dependencies and spatial dependencies. Current statistical models for change over time are typically defined relative to some initial condition, thus skirting the issue of where the first network came from. Additionally, while these longitudinal network models may explain the dynamics of change in the network over time, they do not explain the change in those dynamic…
Social Networks and Social Settings
Lost in translation
Some of the constitutive features of social relations are lost when information naturally produced by sequential social interaction is translated into network ties. Building on core concepts and ideas developed within conversation analysis, in this paper we argue that this happens because the sequential, multimodal and embodied character of social relations can be fully understood only with reference to the sequential constrains that are generate…
Relational event models in network science
Relational event models (REMs) for the analysis of social interaction were first introduced 15 years ago. Since then, a number of important substantive and methodological contributions have produced their progressive refinement and hence facilitated their increased adoption in studies of social and other networks. Today REMs represent a well-established class of statistical models for relational processes. This special issue of Network Science de…
Reliability of relational event model estimates under sampling
We assess the reliability of relational event model (REM) parameters estimated under two sampling schemes: (1) uniform sampling from the observed events and (2) case–control sampling which samples nonevents, or null dyads (“controls”), from a suitably defined risk set. We experimentally determine the variability of estimated parameters as a function of the number of sampled events and controls per event, respectively. Results suggest that REMs ca…
Multilevel social spaces
In this paper, we seek to advance an updated concept of social space that integrates the multilayer and dynamic statistical network methods currently at the disposal of social network researchers. We demonstrate the analytic value of the new concept of social space that we propose with the help of an illustrative analysis of an organizational field involving organizations' external and internal decisions that congeal into a multilevel system of a…
Multiple clocks in network evolution
Relational event models shift the analytical focus away from network ties defined in terms of transitions between mutually exclusive states of connectivity, to bonding processes emerging from observable flows linking senders and receivers of action. In this framework, the possibility to connect social mechanisms of theoretical interest to sequences of observed relational events depends on the relative speed at which these mechanisms operate. Buil…
The Population and Community Ecology of Organizational Founding
Ecological models of organizational founding are proposed in order to investigate the effect of competitive and institutional processes on the founding rates in two populations of co-operative banks in Italy for the period 1936–1989. A number of stochastic specifications of organizational founding rates are estimated to test the effects of density dependence, resource partitioning and community interdependence on the vital dynamics of the organiz…
Team diversity, polarization, and productivity in online peer production
A computational approach to the evolution of competitive strategy
The weakness of the theoretical link between existing micro and macro approaches to the study of organizational behavior is particularly evident when one tries to follow the indications of contemporary theories of organization and analyze competition as an emergent social process. In this paper we present a computational model of how individual competitive behavior evolves into aggregates with complex collective properties which determine the str…
The Population and Community Ecology of Organizational Founding
Ecological models of organizational founding are proposed in order to investigate the effect of competitive and institutional processes on the founding rates in two populations of co-operative banks in Italy for the period 1936–1989. A number of stochastic specifications of organizational founding rates are estimated to test the effects of density dependence, resource partitioning and community interdependence on the vital dynamics of the organiz…
A computational approach to the evolution of competitive strategy
The weakness of the theoretical link between existing micro and macro approaches to the study of organizational behavior is particularly evident when one tries to follow the indications of contemporary theories of organization and analyze competition as an emergent social process. In this paper we present a computational model of how individual competitive behavior evolves into aggregates with complex collective properties which determine the str…
Why are some more peer than others? Evidence from a longitudinal study of social networks and individual academic performance
The Garbage Can Model of Organizational Choice
The year 2012 is the 40th anniversary of the publication of Cohen, March, and Olsen's influential article "The Garbage Can Model of Organizational Choice", which offered a major new perspective on organizational decision making. To celebrate this enduring paradigm, its impact on our understanding of organizational decision making, and the broad streams of research it has influenced, this collection of papers provides a rich demonstration of the i…
“Trust Me”
The dual network structure of organizational problem solving
A model for the multiplex dynamics of two-mode and one-mode networks, with an application to employment preference, friendship, and advice
The Network Dynamics of Social Status
The distinction between network theories and theories of networks is particularly salient in studying social status because social status is both a consequence and an antecedent of network ties. Status is a consequence of network ties because it is conferred by interdependent acts of deference connecting a sender and a recipient. Status is also an antecedent of network ties because it affects individual preferences for social interaction which pr…
Social Networks and Social Settings
Quality of Care and Interhospital Collaboration
OBJECTIVES: We examine the dynamics of patient-sharing relations within an Italian regional community of 35 hospitals serving approximately 1,300,000 people. We test whether interorganizational relations provide individual patients access to higher quality providers of care. RESEARCH DESIGN AND METHODS: We reconstruct the complete temporal sequence of the 3461 consecutive interhospital patient-sharing events observed between each pair of hospital…
Computer Simulation
Computer simulation is a distinctive approach to the representation of organizational theories. In this article I discuss some of the premises and promises of computer simulation as an approach to studying organizations.
Simultaneous modeling of initial conditions and time heterogeneity in dynamic networks
In dynamic networks, the presence of ties are subject both to endogenous network dependencies and spatial dependencies. Current statistical models for change over time are typically defined relative to some initial condition, thus skirting the issue of where the first network came from. Additionally, while these longitudinal network models may explain the dynamics of change in the network over time, they do not explain the change in those dynamic…
The embeddedness of organizational performance
Assimilation and differentiation
Introduction to multilevel social networks
The Network Dynamics of Status
Using longitudinal data that we have collected on friendship and advice relations in a cohort of MBA students, we examine how status affects the dynamics of network ties among peers. Estimates of Stochastic Actor-Oriented Models (SAOMs) suggest that status is a consequence of network ties because over time the level of status attributed to individual students by other students tends to the average level of status attributed to their network partn…
Multilevel social spaces
In this paper, we seek to advance an updated concept of social space that integrates the multilayer and dynamic statistical network methods currently at the disposal of social network researchers. We demonstrate the analytic value of the new concept of social space that we propose with the help of an illustrative analysis of an organizational field involving organizations' external and internal decisions that congeal into a multilevel system of a…
Investigating the Temporal Dynamics of Interorganizational Exchange
Previous research on interaction behavior among organizations (resource exchange, collaboration, communication) has typically aggregated those behaviors over time as a network of organizational relationships. The authors instead study structural-temporal patterns in organizational exchange, focusing on the dynamics of reciprocation. Applying this lens to a community of Italian hospitals during 2003–7, the authors observe two mechanisms of interor…
The free encyclopedia that anyone can dispute
Some days are better than others
Beyond homophily
We consider the specification of effects of numerical actor attributes, having an interval level of measurement, in statistical models for directed social networks. A fundamental mechanism is homophily or assortativity, where actors have a higher likelihood to be tied with others having similar values of the variable under study. But there are other mechanisms that may also play a role in how the attribute values of two actors influence the likel…
Reliability of relational event model estimates under sampling
We assess the reliability of relational event model (REM) parameters estimated under two sampling schemes: (1) uniform sampling from the observed events and (2) case–control sampling which samples nonevents, or null dyads (“controls”), from a suitably defined risk set. We experimentally determine the variability of estimated parameters as a function of the number of sampled events and controls per event, respectively. Results suggest that REMs ca…
Team diversity, polarization, and productivity in online peer production
Dynamic network analysis of contact diaries
Analyzing two-mode networks linking actors to events they attend may help to uncover the structure and evolution of social networks. This classic social network insight is particularly valuable in the analysis of data extracted from contact diaries where contact events produce — and at the same time are the product of relations among participants. Contact events may comprise any number of actors meeting at a specific point in time. In this paper …
A network centrality bias
Combining the results of two empirical studies, we investigate the role of alters' motivation in explaining change in ego's network position over time. People high in communal motives, who are prone to supportive and altruistic behavior in their interactions with others as a way to gain social acceptance, prefer to establish ties with co-workers occupying central positions in organizational social networks. This effect results in a systematic net…
Computer Science (27 works) · Sociology (18 works) · Psychology (17 works) · Social Psychology (13 works) · Opinion Dynamics and Social Influence (11 works) · Complex Network Analysis Techniques (10 works) · Economics (10 works) · Mathematics (10 works) · Social Capital and Networks (10 works) · Artificial Intelligence (9 works)