We analyze how sharing rules affect Nash equilibria in Bertrand games, where the sharing of profits at ties is a decisive assumption. Necessary conditions for either positive or zero equilibrium profits are derived. Zero profit equilibria are shown to exist under weak conditions if the sharing rule is “sign-preserving”. For Bertrand markets we define the class of “expectation sharing rules”, wh...

We provide direct evidence that people with strong family ties have a lower level of trust in strangers than people with weak family ties, and argue that this association is causal. We also investigate the mechanisms that underlie this effect, and provide evidence that these revolve around the level of outward exposure: factors that limit exposure limit subjects’ experience as well as motivatio...

This paper models the entrepreneurial process as both creation and discovery composed of an iterative two-step process where entrepreneurs create social networks based on subjective expectations about the future effectiveness of those networks, and then choose the innovation to pursue and map a search process to discover how to bring the innovation to fruition. Critical to this process is the m...

Based on social network perspective, we developed a model about the knowledge sharing of communities of practice (CoPs), analyzed the knowledge sharing of CoPs from the view of the network density, network centrality, network structure. And we found out that only the above indexes are kept in appropriately level can stimulate the knowledge sharing in CoPs. The strong ties contribute to the tran...

We examine the communication patterns of millions of anonymized mobile phone users. Based on call records, we construct a communication network where vertices are subscribers and edge weights are defined as aggregated duration of calls, reflecting the strengths of social ties between callers. We observe a coupling between tie strengths and network topology: at the ”local” level, strong ties are...

It is widely established that the levels of generalized trust, norms of reciprocity, and identification (collectively known as relational social capital) in a virtual community have a positive effect on a member’s motivation to contribute knowledge in the community. However, little is known on the antecedents of such relational social capital. This study longitudinally investigates the effects ...

In most social and information systems the activity of agents generates rapidly evolving time-varying networks. The temporal variation in networks' connectivity patterns and the ongoing dynamic processes are usually coupled in ways that still challenge our mathematical or computational modelling. Here we analyse a mobile call dataset and find a simple statistical law that characterize the tempo...

Alesina and Giuliano (J. Econ. Growth, 15(2), 2010) illustrate that strong family ties lead to disruptive socio-economic outcomes including lower geographical mobility and reduced labor force participation of young and female individuals. We extend their analysis by arguing that the effect of strong family ties on economic behavior depends on a country’s level of economic and institutional deve...

Abstract We analyze the causal effect of retirement on individual social relationships using data from Survey Health, Ageing and Retirement in Europe. find that changes composition individual’s network, inducing a substitution between weak (friends or colleagues) strong ties (family), along with an increase intensity surviving ties, there is no network’s size. These are associated higher satisf...