Our approach builds on the baseline definition of simplicity based on word frequency but attempt at defining a more
linguistically motivated notion of simplicity based on lexical semantics considerations. Therefore, in order to operationalize the notion
of simplicity in our system we adopt different strategies depending on the syntactic complexity of the lexical form that forms the substitute.
\begin{itemize}
\item in the trivial case of one-word substitutes or common collocations we use the frequency associated by Wordnet to the lexical form as
metrics to rank the substitutes. For instance, the lexical item \emph{intelligent} is ranked lower that \emph{clever} as it has a lower
frequency in the language (as defined in Wordnet).
\item In the case of multi-words substitutes of bigger syntactic complexity, we apply so-called "relevance" rules
that apply (de)compositional semantic criteria and attempt to identify a unique content word in the substitute that might better approximate the whole lexical form. Thus we assign to the whole lexical form the
frequency associated to the most relevant content word and use it for ranking the whole substitute.
For instance, relevance rules assign to multi-word substitutes such as \emph{most able} or \emph{not able} the same frequency associated
to the content word \emph{able}.
\end{itemize}
We implemented the following steps:
\begin{itemize}
\item A syntactic parser was used to assign Part-Of-Speech to each word of the context and of the substitutes. We used the Stanford Parser.
\item We performed WordSense Tagging so to assign a WordNet sense (WordNet 3.1) to the target words and the substitutes.
We used the Ted Pedersen WordNet-Similarity Package for word sense disambiguation and the JWNL package for information retrieval form WordNet.
\item We defined hand-written rules and apply them to decompose the meaning of a complex structure and identify the most
relevant word conveying the semantics of the whole.
\end{itemize}
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