Answers.Body: <p>The issue is that extractive QA limits the types of questions to ones that have answers that appear <em>exactly</em> in the text.</p>
  <p>For example, consider the question:</p>
  <pre><code>Is Bob considered a good movie director?
  </code></pre>
  <p>It's very unlikely that you're going to have a document that says exactly <code>Bob is a good movie director</code>. But, you might have several documents that talk about the quality of movies that Bob has directed or interviews that discuss how well he works with actors etc. from which you can <em>infer</em> an answer from the totality of the evidence.</p>
  <p>That's not say that extractive systems are always worse, you're just faced with the classic trade-off of a restrictive but predictable system versus a more flexible system that may e.g., hallucinate.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-02T01:18:21.933Z
Answers.LastActivityDate: 2024-02-02T02:07:53.813Z
Answers.LastEditDate: 2024-02-02T02:07:53.813Z
Answers.UserDisplayName: Alexander Wan
Body: <p>If the concern with using generative models for question answering is that these models aren't always producing factual information, why is it that people are using these models with Retrieval Augmented Generation (Open Generative QA/Closed Generative QA), rather than using a transformers-based extractive QA model that can refer users to the potential answer from actual text documentation?</p>
  
Tags: <chatgpt><question-answering>
Title: Why is generative QA + RAG so popular when extractive QA models exist that can provide factual information?
UserDisplayName: Celi Manu
ThreadText: # Why is generative QA + RAG so popular when extractive QA models exist that can provide factual information?
  
  (Asked by: username_0 on 2024-02-01)
  
  If the concern with using generative models for question answering is that these models aren't always producing factual information, why is it that people are using these models with Retrieval Augmented Generation (Open Generative QA/Closed Generative QA), rather than using a transformers-based extractive QA model that can refer users to the potential answer from actual text documentation?
  
  **Tags:** chatgpt, question-answering
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2024-02-02. Score: 1 | Accepted answer
  
  The issue is that extractive QA limits the types of questions to ones that have answers that appear exactly in the text.
  For example, consider the question:
  Is Bob considered a good movie director?
  
  It's very unlikely that you're going to have a document that says exactly Bob is a good movie director. But, you might have several documents that talk about the quality of movies that Bob has directed or interviews that discuss how well he works with actors etc. from which you can infer an answer from the totality of the evidence.
  That's not say that extractive systems are always worse, you're just faced with the classic trade-off of a restrictive but predictable system versus a more flexible system that may e.g., hallucinate.
  
  
  ---
  
  