Exploring Annotation Taxonomy In Grouped Bar Charts: A Qualitative Classroom Study

Annotations are an essential part of data analysis and communication in visualizations, which focus a reader’s attention on critical visual elements (e.g., an arrow that emphasizes a downward trend in a bar chart). Annotations enhance comprehension, mental organization, memorability, user engagement, and interaction and are crucial for data externalization and exploration, collaborative data analysis, and narrative storytelling in visualizations. However, we have identified a general lack of understanding of how people annotate visualizations to support effective communication. In this study, we evaluate how visualization students annotate grouped bar charts when answering high-level questions about the data. The resulting annotations were qualitatively coded to generate a taxonomy of how they leverage different visual elements to communicate critical information. We found that the annotations used significantly varied by the task they were supporting and that whereas several annotation types supported many tasks, others were usable only in special cases. We also found that some tasks were so challenging that ensembles of annotations were necessary to support the tasks sufficiently. The resulting taxonomy of approaches provides a foundation for understanding the usage of annotations in broader contexts to help visualizations achieve their desired message.

Md Dilshadur Rahman, Ghulam Jilani Quadri, Danielle Albers Szafir, and Paul Rosen. Exploring Annotation Taxonomy In Grouped Bar Charts: A Qualitative Classroom Study. To appear in Information Visualization Journal, 2024.

@article{rahman2024annotationInfovis,
  title = {Exploring Annotation Taxonomy in Grouped Bar Charts: A Qualitative Classroom
    Study},
  author = {Rahman, Md Dilshadur and Quadri, Ghulam Jilani and Szafir, Danielle Albers
    and Rosen, Paul},
  journal = {To appear in Information Visualization Journal},
  year = {2024},
  abstract = {Annotations are an essential part of data analysis and communication in
    visualizations, which focus a reader’s attention on critical visual elements (e.g., an
    arrow that emphasizes a downward trend in a bar chart). Annotations enhance
    comprehension, mental organization, memorability, user engagement, and interaction and
    are crucial for data externalization and exploration, collaborative data analysis, and
    narrative storytelling in visualizations. However, we have identified a general lack of
    understanding of how people annotate visualizations to support effective communication.
    In this study, we evaluate how visualization students annotate grouped bar charts when
    answering high-level questions about the data. The resulting annotations were
    qualitatively coded to generate a taxonomy of how they leverage different visual
    elements to communicate critical information. We found that the annotations used
    significantly varied by the task they were supporting and that whereas several
    annotation types supported many tasks, others were usable only in special cases. We also
    found that some tasks were so challenging that ensembles of annotations were necessary
    to support the tasks sufficiently. The resulting taxonomy of approaches provides a
    foundation for understanding the usage of annotations in broader contexts to help
    visualizations achieve their desired message.}
}