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authorJean Pouget-Abadie <jean.pougetabadie@gmail.com>2015-05-07 21:25:36 -0400
committerJean Pouget-Abadie <jean.pougetabadie@gmail.com>2015-05-07 21:25:36 -0400
commit4110319283b3b5b667d215bd44f23f8cd1a7cf46 (patch)
tree87826e66df3e10ffbf427eb53c621b32f0ceb02d /paper/sections/model.tex
parent16cee067526887f62dc725612d7f34730fddb447 (diff)
downloadcascades-4110319283b3b5b667d215bd44f23f8cd1a7cf46.tar.gz
broke something w/ references + changed RE paragraph
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1 files changed, 6 insertions, 9 deletions
diff --git a/paper/sections/model.tex b/paper/sections/model.tex
index b478e94..acec974 100644
--- a/paper/sections/model.tex
+++ b/paper/sections/model.tex
@@ -192,7 +192,7 @@ Generalized Linear Cascade model with inverse link function $f:z\mapsto
1-e^{-\epsilon\cdot z}$.
\subsubsection{Logistic Cascades}
-
+\label{sec:logistic_cascades}
Consider the specific case of ``logistic cascades'' (where $f$ is the logistic
function). This model captures the idea that there is a threshold around which
each additional neighbor's contribution becomes significant: logistic
@@ -201,10 +201,7 @@ Threshold model~\cite{Kempe:03}. As we will see later in the
analysis, the Hessian of our optimization program simplifies in the case of a
logistic inverse link function to $\nabla^2\mathcal{L}(\theta^*) =
\frac{1}{|\mathcal{T}|}XX^T$ where $X$ is the observation matrix $[x^1 \ldots
-x^\mathcal{|T|}]$. The (RE)-condition we introduce subsequently is then
-equivalent to the assumption made in the Lasso analysis of~\cite{bickel:2009}.
-
-
+x^\mathcal{|T|}]$.
% \subsection{The Linear Threshold Model}
@@ -234,10 +231,10 @@ equivalent to the assumption made in the Lasso analysis of~\cite{bickel:2009}.
\begin{figure}
\includegraphics[scale=.4]{figures/drawing.pdf}
- \caption{Illustration of the sparse-recovery approach: the measurement matrix
- is known, as is a Bernoulli realization of the matrix-vector product via the
-non-linear transformation induced by $f$. Our objective is to recover the
-unknown weight vector $\theta_i$ for each node $i$.}
+ \caption{Illustration of the sparse-recovery approach. Our objective is to
+ recover the unknown weight vector $\theta_j$ for each node $j$. We observe a
+Bernoulli realization of the $f$ transform of the matrix-vector product, where
+the measurement matrix encodes which nodes are ``contagious''}
\end{figure}