Structure of Postings List
– Postings list consists of posting elements
– Posting elements contain document identifier (DocID)
– Posting elements contain frequency information (Term Frequency)
– Posting elements contain position information
– Additional metadata may include document titles, headings, or other relevant information
Variants of Postings List
– Inverted index: Form of postings list that points from terms to documents
– Impact-ordered postings: Lists ordered by weight or impact of term in document
– Positional postings lists: Enhanced postings lists with position information for phrase queries and proximity searches
References
– Büttcher, Stefan; Clarke, Charles L. A.; Cormack, Gordon V. (2016): ‘Information retrieval: implementing and evaluating search engines’
– First MIT Press paperbacked
– Cambridge, Massachusetts London, England: The MIT Press
– ISBN978-0-262-52887-0
– Retrieved from https://en.wikipedia.org/w/index.php?title=Postings_list&oldid=1189633289
Application of Postings Lists
– Postings lists are used during search queries
– IR system retrieves postings lists for each term in query
– Postings lists help determine relevant documents
– Frequency and positions of terms are considered
– Structure of postings lists can vary based on application
Categories
– Data structures
– Information retrieval
The postings list is a data structure commonly used in information retrieval (IR) systems to store indexing information about a corpus. It is central to the design and efficiency of search engines and database management systems that need to retrieve information rapidly.
At the bare minimum, a postings list is associated with a term from a document and records the places where that term appears. Each term found in documents within a corpus is mapped to a corresponding postings list containing information such as the documents the term appears in and often the positions within those documents.
