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Question Generator

Question Answering systems are trained to find an answer given a question and a document; but with the recent advances in generative NLP, there are now models that can read a document and suggest questions that can be answered by that document. All this power is available to you now via the QuestionGenerator class.

QuestionGenerator models can be trained using Question Answering datasets. Instead of predicting answers, the QuestionGenerator takes the document as input and is trained to output the questions.

Note: The QuestionGenerator is different to the Generator. The QuestionGenerator receives only documents as input and returns questions as output while the Generator class is an alternative to the Reader. It takes a question and documents as input and returns an answer.

Stand-Alone Usage

from haystack.nodes import QuestionGenerator
text = """Python is an interpreted, high-level, general-purpose programming language. Created by Guido van Rossum
and first released in 1991, Python's design philosophy emphasizes code
readability with its notable use of significant whitespace."""
qg = QuestionGenerator()
result = qg.generate(text)

The output will look like this:

[' Who created Python?',
' When was Python first released?',
" What is Python's design philosophy?"]

Ready-Made Pipelines

In Haystack, there are 2 pipeline configurations that are already encapsulated in its own class.

  • QuestionGenerationPipeline
  • QuestionAnswerGenerationPipeline

Have a look at our ready-made pipelines page to learn more about them. Check out the question generation tutorial to start using them.

Use Case: Auto-Suggested Questions

Generated questions can help users get closer to the information that they are looking for. Search engines now present auto-suggested questions to your top search results and even present suggested answers. It is possible to build this same functionality in Haystack using the QuestionGenerator.

After your Retriever has returned some candidate documents, you can run the QuestionGenerator to suggest more answerable questions. By presenting these generated questions to your users, you can give them a sense of other facts and topics that are present in the documents. You can go even on step further by predicting answers to these questions with a Reader or Generator.

Use Case: Human in the Loop Annotation

A QuestionGenerator can enable different annotation workflows. For example, given a text corpus, you could use the QuestionGenerator to create questions, but you can also use then use a Reader to predict answers.

Correct QA pairs created in this manner might not be so effective in retraining your Reader model. However, correcting wrong QA pairs creates training samples that your model found challenging. These examples are likely to be impactful when it comes to retraining. This is also a quicker workflow than having annotators generate both question and answer.