This paper presents discursive patinas, a technique to visualize discussions onto data visualizations, inspired by how people leave traces in the physical world. While data visualizations are widely discussed in online communities and social media, comments tend to be displayed separately from the visualization and we lack ways to relate these discussions back to the content of the visualization, e.g., to situate comments, explain visual patterns, or question assumptions. In our visualization annotation interface, users can designate areas within the visualization. Discursive patinas are made of overlaid visual marks (anchors), attached to textual comments with category labels, likes, and replies. By coloring and styling the anchors, a meta visualization emerges, showing what and where people comment and annotate the visualization. These patinas show regions of heavy discussions, recent commenting activity, and the distribution of questions, suggestions, or personal stories. We ran workshops with 90 students, domain experts, and visualization researchers to study how people use anchors to discuss visualizations and how patinas influence people's understanding of the discussion. Our results show that discursive patinas improve the ability to navigate discussions and guide people to comments that help understand, contextualize, or scrutinize the visualization. We discuss the potential of anchors and patinas to support discursive engagements, including critical readings of visualizations, design feedback, and feminist approaches to data visualization.

翻译：本文提出“话语包浆”技术，将讨论内容可视化叠加到数据可视化图表上，其灵感来源于人们在物理世界中留下痕迹的行为方式。尽管数据可视化在在线社区和社交媒体中被广泛讨论，但评论往往与可视化图表分离显示，我们缺乏将这些讨论与可视化内容关联的方法，例如定位评论位置、解释视觉模式或质疑前提假设。在我们的可视化标注界面中，用户可以在可视化图表内划定特定区域。话语包浆由叠加的视觉标记（锚点）构成，这些锚点关联着带有类别标签、点赞和回复的文本评论。通过对锚点进行着色和样式设计，会形成元可视化层，展示人们评论和标注可视化图表的内容与位置。这些包浆能显示密集讨论区域、近期评论活动，以及问题、建议或个人故事的分布情况。我们通过工作坊形式对90名学生、领域专家和可视化研究者进行研究，探索人们如何使用锚点讨论可视化图表，以及包浆如何影响人们对讨论的理解。研究结果表明，话语包浆能提升讨论导航能力，并引导人们找到有助于理解、情境化或审视可视化图表的评论。我们探讨了锚点与包浆支持话语参与的潜力，包括可视化批判性解读、设计反馈以及数据可视化的女性主义研究方法。