6 Question & Answer

The implementation of question-and-answer (Q&A) queries is another valuable functionality provided by the HistText library. This feature enables researchers to target and extract specific content from natural-language texts based on user-defined queries. By formulating questions or prompts, researchers can use the Q&A feature to extract data from documents in natural language. Q&A functions in HistText are particularly effective for retrieving biographical information.

It’s important to note that these models may not be fully functional and could time out on long texts, especially when multiple questions are asked simultaneously.

Two models are currently available in HistText: one for Chinese and one for English. You can use the list_qa_models() to list the available models:

histtext::list_qa_models()

6.1 Basic usage

The most basic use is to ask a single question:

imh_en_df <- histtext::search_documents('"member of party"', "imh-en")

histtext::qa_on_corpus(imh_en_df, "What is his full name?", "imh-en")

Alternatively, you can ask multiple variants of a question:

histtext::qa_on_corpus(imh_en_df, c("What is his full name?", "What name?"), "imh-en")

6.2 More complex usage

A more advanced usage of Q&A can be achieved when questions depend on previous questions:

questions <- list("name:full" = c("What is his full name?", "What name?"),
                  "education:location" = c("Where {name:full} study at?", "Where study at?"))
histtext::qa_on_corpus(imh_en_df, questions, "imh-en")

ou can also specify the number of answers that a question should be allowed to produce:

histtext::qa_on_corpus(imh_en_df, questions, "imh-en", max_answers = list("education:location" = 2))

Examples of questions on which models where trained with can be accessed using the following functions:

histtext::biography_questions("en")
histtext::biography_questions("zh")

Please avoid using directly the output of this function as an input to the Q&A functions. The amount of questions will overwhelm the server and your query will probably time-out in many cases. You can however take a small subset of these.