Information Retrieval Questions Medium
Query expansion using pseudo-relevance feedback is a technique used in information retrieval to improve the effectiveness of search queries. It involves expanding the original query by incorporating additional terms or concepts that are likely to be relevant to the user's information needs.
The process begins by submitting the user's initial query to the search engine. The search engine then retrieves a set of top-ranked documents that are considered to be relevant to the query. These documents are known as the "pseudo-relevant" documents.
Next, the search engine analyzes the content of these pseudo-relevant documents to identify terms or concepts that are frequently occurring. These terms are assumed to be indicative of the user's information needs and are selected for query expansion.
The selected terms are then added to the original query, either as additional keywords or as synonyms. This expanded query is then resubmitted to the search engine, which retrieves a new set of documents based on the expanded query.
The process of query expansion using pseudo-relevance feedback aims to capture the user's information needs more accurately by incorporating terms that are likely to be relevant. By expanding the query, the search engine can retrieve a broader range of documents that may have been missed by the original query.
This technique has been found to be particularly effective in overcoming the limitations of the user's initial query, such as ambiguity or lack of specificity. It helps to refine the search results and improve the overall precision and recall of the information retrieval system.
However, it is important to note that query expansion using pseudo-relevance feedback is not without its challenges. The selection of relevant terms from the pseudo-relevant documents can be subjective and may introduce noise or irrelevant terms into the expanded query. Additionally, the effectiveness of this technique heavily relies on the quality of the initial search results and the relevance judgments made by the search engine.