Data analysis often involves the comparison of complex objects. With the ever increasing amounts and complexity of data, the demand for systems to help with these comparisons is also growing. Increasingly, information visualization tools support such comparisons explicitly, beyond simply allowing a viewer to examine each object individually. In this paper, we argue that the design of information visualizations of complex objects can, and should, be studied in general, that is independently of what those objects are. As a first step in developing this general understanding of comparison, we propose a general taxonomy of visual designs for comparison that groups designs into three basic categories, which can be combined. To clarify the taxonomy and validate its completeness, we provide a survey of work in information visualization related to comparison. Although we find a great diversity of systems and approaches, we see that all designs are assembled from the building blocks of juxtaposition, superposition and explicit encodings. This initial exploration shows the power of our model, and suggests future challenges in developing a general understanding of comparative visualization and facilitating the development of more comparative visualization tools.

翻译：数据分析通常涉及复杂对象的比较。随着数据量和复杂性的不断增加，对辅助比较系统的需求也在增长。信息可视化工具正越来越多地明确支持此类比较，而非仅让用户逐一审视每个对象。本文认为，复杂对象的信息可视化设计理应且能够被一般性地研究，即独立于这些对象的具体形式。为发展这种比较的通用理解，我们提出了一种比较可视化设计的通用分类法，将设计归为可组合的三大基本类别。为阐明分类法并验证其完整性，我们系统综述了信息可视化领域中与比较相关的工作。尽管发现系统和方法的多样性显著，但所有设计均由并置、叠加和显式编码三大构建模块组合而成。这一初步探索揭示了本模型的效力，并提出了发展比较可视化通用理解及促进更多比较可视化工具开发的未来挑战。