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@@ -272,19 +272,31 @@ priors. We can:
\item Take into account common graph structures, such as triangles, clustering
\end{itemize}
-A common prior for graph is the ERGM model~\cite{}, defined by feature vector
-$s(G)$ and by the probability distribution:
+A common prior for graph is the Exponential Random Graph Model (ERGM), which
+allows flexible representations of networks and Bayesian inference. The
+distribution of an ERGM family is defined by feature vector $s(G)$ and by the
+probability distribution:
$$P(G | \Theta) \propto \exp \left( s(G)\cdot \Theta \right)$$
+Though straightforward MCMC could be applied here, recent
+work~\cite{caimo2011bayesian, koskinen2010analysing, robins2007recent} has shown
+that ERGM inference has slow convergence and lack of robustness, developping
+better alternatives to naive MCMC formulations. Experiments using such a prior
+are ongoing, but we present only simple product distribution-type priors here.
+
\paragraph{Inference}
We can sample from the posterior by MCMC\@. This might not be the fastest
solution however. We could greatly benefit from using an alternative method:
\begin{itemize}
-\item EM\@. This approach was used in \cite{linderman2014discovering} to learn
+\item EM\@. This approach was used in \cite{linderman2014discovering,
+simma2012modeling} to learn
the parameters of a Hawkes process, a closely related inference problem.
\item Variational Inference. This approach was used
in~\cite{linderman2015scalable} as an extension to the paper cited in the
-previous bullet point.
+previous bullet point. Considering the scalabilty of their approach, we hope to
+apply their method to our problem here, due to the similarity of the two
+processes, and to the computational constraints of running MCMC over a large
+parameter space.
\end{itemize}