We study a general preferential attachment and Pólya's urn model. At each step a new vertex is introduced, which can be connected to at most one existing vertex. If it is disconnected, it becomes a pioneer vertex. Given that it is not disconnected, it joins an existing pioneer vertex with...

We study the probability that two or more agents can attain common knowledge of nontrivial events when the size of the state space grows large. We adopt the standard epistemic model where the knowledge of an agent is represented by a partition of the state space. Each agent is endowed with a...

Since 1990, Belgium has managed to bring down greenhouse gas emissions in most domains of economic activity. Road transport, as in many other countries, is a notable exception to this pattern: emissions have steadily increased, driven by an ever higher consumption of petrol and diesel. Even...

Innovative startups are frequently acquired by large incumbent firms. On the one hand, these acquisitions provide an incentive for startup creation and may transfer ideas to more efficient users. On the other hand, incumbents might acquire startups just to "kill" their ideas, and acquisitions...

What are the effects of a housing bubble on the rest of the economy? We show that if firms and banks face collateral constraints, a housing bubble initially raises credit demand by housing firms while leaving credit supply unaffected. It therefore crowds out credit to non-housing firms. If time...