  Knowledge-grounded dialogue is a task of generating an informative response
based on both the dialogue history and external knowledge source. In general,
there are two forms of knowledge: manually annotated knowledge graphs and
knowledge text from website. From various evaluation viewpoints, each type of
knowledge has advantages and downsides. To further distinguish the principles
and determinants from the intricate factors, we conduct a thorough experiment
and study on the task to answer three essential questions. The questions
involve the choice of appropriate knowledge form, the degree of mutual effects
between knowledge and the model selection, and the few-shot performance of
knowledge. Supported by statistical shreds of evidence, we offer conclusive
solutions and sensible suggestions for directions and standards of future
research.
