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\begin{itemize}
\item When a user sees the reported value $z$ of the mechanism, he may take $z$ as it is, or, based on his prior knowledge, he may guess another value $w$. We say that the user {\color{red} remaps} $z$ into $w$. 
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Summarizing, we have: 
\item $\cal X$, the set of databases, with associated random variable $X$
\item $\cal Y$, the set of true answers to the query $f$. Associated random variable $Y$
\item $\cal Z$, the set of reported answers to the query $f$ (after we apply the noise). Associated random variable $Z$
\item $\cal W$, the set of guesses. Associated random variable $W$. $\cal W$ often coincides with $\cal Y$, but $W$ usually does not coincide with $Y$.
\end{itemize}
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