Natural Language Interfaces for Data Analysis with Visualization: Considering What Has and Could Be Asked.

Natural language is emerging as a promising interaction paradigm for data analysis with visualization. Designing and implementing Natural Language Interfaces (NLIs) is a challenging task, however. In addition to being able to process and understand natural language expressions, NLIs for data visuailzation must consider other factors including input modalities, providing input affordances, and explaining system results, among others. In this article, we examine existing NLIs for data analysis with visualization, and compare and contrast them based on the tasks they allow people to perform. We discuss open research opportunities and themes for emerging NLIs in the visualization community. We also provide examples from the existing literature in the broader HCI community that may help explore some of the highlighted themes for future work. Our goal is to assist readers to understand the subtleties and challenges in designing NLIs and encourage the community to think further about NLIs for data analysis with visualization.