Micro-Macro Links and Microfoundations in Sociology focuses on two main issues in sociology. Firstly, how macro-conditions can explain macro-outcomes mediated by actor behaviour at the micro-level (micro-macro links). Secondly, how alternative micro-models affect macro-outcomes (microfoundations). The contributions reflect key features of micro-macro modelling in sociology as well as recent progress in this field. The chapters address core features of explanations of social phenomena using micro-macro models, the problem of cooperation, heterogeneity of actors, structural balance, opinion formation, segregation, and problems of micro-macro models that are based on rational choice assumptions. Moreover, the contributions show how different research methods can be applied fruitfully, such as laboratory experiments, equilibrium analysis, and agent-based modelling. As a result, the book can be a guide for graduate students who want to develop their skills in building micro-macro models. In addition, the book provides specialists of the different substantive research areas with up-to-date new developments in their research area. This book was originally published as a special issue of Journal of Mathematical Sociology.

Micro-Macro Links and Microfoundations in Sociology focuses on two main issues in sociology. Firstly, how macro-conditions can explain macro-outcomes mediated by actor behaviour at the micro-level (micro-macro links). Secondly, how alternative micro-models affect macro-outcomes (microfoundations). The contributions reflect key features of micro-macro modelling in sociology as well as recent progress in this field. The chapters address core features of explanations of social phenomena using micro-macro models, the problem of cooperation, heterogeneity of actors, structural balance, opinion formation, segregation, and problems of micro-macro models that are based on rational choice assumptions. Moreover, the contributions show how different research methods can be applied fruitfully, such as laboratory experiments, equilibrium analysis, and agent-based modelling. As a result, the book can be a guide for graduate students who want to develop their skills in building micro-macro models. In addition, the book provides specialists of the different substantive research areas with up-to-date new developments in their research area. This book was originally published as a special issue of Journal of Mathematical Sociology.

Social Networks and Trust discusses two possible explanations for the emergence of trust via social networks. If network members can sanction untrustworthiness of actors, these actors may refrain from acting in an untrustworthy manner. Moreover, if actors are informed regularly about trustworthy behavior of others, trust will grow among these actors.
A unique combination of formal model building and empirical methodology is used to derive and test hypotheses about the effects of networks on trust. The models combine elements from game theory, which is mainly used in economics, and social network analysis, which is mainly used in sociology.
The hypotheses are tested (1) by analyzing contracts in information technology transactions from a survey on small and medium-sized enterprises and (2) by studying judgments of subjects in a vignette experiment related to hypothetical transactions with a used-car dealer.

Social Networks and Trust discusses two possible explanations for the emergence of trust via social networks. If network members can sanction untrustworthiness of actors, these actors may refrain from acting in an untrustworthy manner. Moreover, if actors are informed regularly about trustworthy behavior of others, trust will grow among these actors.
A unique combination of formal model building and empirical methodology is used to derive and test hypotheses about the effects of networks on trust. The models combine elements from game theory, which is mainly used in economics, and social network analysis, which is mainly used in sociology.
The hypotheses are tested (1) by analyzing contracts in information technology transactions from a survey on small and medium-sized enterprises and (2) by studying judgments of subjects in a vignette experiment related to hypothetical transactions with a used-car dealer.

The problem of cooperation is one of the core issues in sociology and social science more in general. The key question is how humans, groups, organizations, institutions, and countries can avoid or overcome the collective good dilemmas that could lead to a Hobbesian "war of all against all". The chapters in this book provide state of the art examples of research on this crucial topic. These include theoretical, laboratory, and field studies on trust and cooperation, thereby approaching the issue in three complementary and synergetic ways. The theoretical work covers articles on trust and control, reputation formation, and paradigmatic articles on the benefits and caveats of abstracting reality into models. The laboratory studies test the implications of different models of trust and reputation, such as the effects of social and institutional embeddedness and the potentially emerging inequalities this may cause. The field studies test these implications in applied settings such as business purchasing and supply, informal care, and different kinds of collaboration networks. This book is exemplary for rigorous social science. The focus is on effects of social conditions, in particular different forms of social and institutional embeddedness, on social outcomes at the macro level. Modelling efforts are applied to connect social conditions to social outcomes through micro-level behavior in ways that are easily overlooked when argumentation is intuitive and impressionistic. The book sets forth a mixed-method approach by applying different empirical methods to test hypotheses about similar questions. Several contributions re-evaluate the theoretical strengths and weaknesses following from the laboratory and field studies. Improving the theory in light of these findings facilitates pushing the boundaries of social science .

There is one thing that moves online consumers to click add to cart, that allows sellers to accept certain forms of online payment, and that makes online product reviews meaningful: trust. Without trust, online interactions can t advance. But how is trust among strangers established on the Internet? What role does reputation play in the formation of online trust? In eTrust, editors Karen Cook, Chris Snijders, Vincent Buskens, and Coye Cheshire explore the unmapped territory where trust, reputation, and online relationships intersect, with major implications for online commerce and social networking. eTrust uses experimental studies and field research to examine how trust in anonymous online exchanges can create or diminish cooperation between people. The first part of the volume looks at how feedback affects online auctions using trust experiments. Gary Bolton and Axel Ockenfels find that the availability of feedback leads to more trust among one-time buyers, while Davide Barrera and Vincent Buskens demonstrate that, in investment transactions, the buyer s own experience guides decision making about future transactions with sellers. The field studies in Part II of the book examine the degree to which reputation facilitates trust in online exchanges. Andreas Diekmann, Ben Jann, and David Wyder identify a reputation premium in mobile phone auctions, which not only drives future transactions between buyers and sellers but also payment modes and starting bids. Chris Snijders and Jeroen Weesie shift focus to the market for online programmers, where tough competition among programmers allows buyers to shop around. The book s third section reveals how the quality and quantity of available information influences actual marketplace participants. Sonja Utz finds that even when unforeseen accidents hinder transactions lost packages, computer crashes the seller is still less likely to overcome repercussions from the negative feedback of dissatisfied buyers. So much of our lives are becoming enmeshed with the Internet, where ordinary social cues and reputational networks that support trust in the real world simply don t apply. eTrust breaks new ground by articulating the conditions under which trust can evolve and grow online, providing both theoretical and practical insights for anyone interested in how online relationships influence our decisions."