Problems in network archaeology: root finding and broadcasting
Gábor Lugosi (ICREA - U. Pompeu Fabra)

Large networks are often naturally modeled by random processes in which nodes of the network are added sequentially, according to some stochastic rule. Uniform and preferential attachment trees are among the simplest examples of such dynamically growing networks. The statistical problems we address in this talk regard discovering the past of the network when a present-day snapshot is observed. We present results that show that, even in gigantic networks, a lot of information is preserved from the very early days. In particular, we discuss the problem of finding the root and the broadcasting problem.