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{{{#!latex2
\begin{definition}
An information retrieval model is a quadruple $D,Q,F,R(q_i , d_j))$ where
\begin{numbering}
\item $D$ is a set composed of logical views (or representations) for the documents in the collection.
\item $Q$ is a set composed of logical views (or representations) for the user information needs. Such representations are called queries
\item $F$ is a framework for modeling document representations, queries and their relationships.
\item $R(q_i,d_j)$ is a ranging function wich associates a real number with a query $q_i \in Q$ and a document represenation $d_j \in D$. Such ranking defines an ordering among the documents with regard to the query $q_i$.
\end{numbering}
\end{definition}

Chapter 1 + Section 2.1 Introduction


attachment:InformationRetreivalProcess.jpg

Information Retrieval Process


  • Three Models of Browsing
    • Flag
    • Structure guided
    • Hypertext

Section 2.2 A taxonomy of Information Retrieval Models

  • Predicting which documents are relevant is usaually dependent on a ranking algorithm.

  • The three classic models in information retreival are:
    • Boolean Model: In the boolean model documents and queries are represented as sets of index terms, thus we say this model is a set theoretic model

    • Vector Model: In the vector model documents and queries are represented as vectors in a t-dimensional space, thus we say that the model is algebraic.

    • Probabilistic Model: The framework for modeling document and query representations is based on probability theory, and thus we sat that the model is prababilistic.

Section 2.3 Retrieval: Ad hoc and Filtering

unl/Csce810Chapter2 (last edited 2020-01-26 18:49:25 by scot)