Conversational agent with common-sense: Responding to nonsensical statements

• Author / Creator

  Konar, Anandh Perumal

• Conversational agents, also known as chatbots, are designed to have a real-time conversation with humans. Closed domain chatbots are limited to a specific task they’re designed to do. They can be rule-based or information retrieval based chatbots while open domain chatbots are meant to mimic humans in conversation. For a conversational agent to have a human-like conversation, the agent needs to generate grammatically correct and coherent output relative to the input. However, it is also crucial for the agent to have common sense and be equipped with basic facts about the world. For example, consider the following statement: “He gave birth to a baby.” For humans, it is common sense that males cannot give birth. Therefore, the given statement is nonsensical. However, for a system, it is challenging to distinguish between sensical and nonsensical statements.
  Moreover, it is even more challenging for a system to generate an explanation stating why the given statement is nonsensical. We propose UNION, a unified end-to-end framework, to generate a meaningful explanation to a given nonsensical statement that utilizes several existing commonsense datasets to allows a model to learn more dynamically under the scope of commonsense reasoning. To perform model selection efficiently, accurately, and promptly, we also propose a couple of auxiliary automatic evaluation metrics so that we can extensively compare the models from different perspectives. Our submitted system results in an excellent performance in the proposed metrics. It outperforms its competitors with the highest achieved score of 2.10 for human evaluation while maintaining a BLEU score of 15.7.

• Subjects / Keywords

  • common sense
  • response generation
  • chatbots
  • nonsensical statements
  • conversational agent

• Graduation date

  Fall 2020

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-bv31-kt07

• License

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