Although physical artifacts that represent data have been used for centuries, the research field –known as data physicalization– has only recently gained traction. Compared to data visualization, there is no established vocabulary for analysing and discussing the properties of physicalizations. Through a grounded analysis of examples and literature, we propose a comprehensive design vocabulary, which consist of three separate, but connected parts:
‘explicit variables’
,
‘implicit properties’
, and
‘consequential aspects’
. Explicit variables build on visual variables known from visualization and extend it to account for physicalization’s multi-modal nature. Implicit properties concern elements which are central to the design intention and user experience of physicalizations, yet are not a result of ‘explicit’ encoding strategies. Finally, consequential aspects refer to unintentional effects of design decisions, that influence how a physicalization is experienced. Our work illustrates how physicalizations incorporate opportunities and challenges that are not afforded in other data representations, such as embodiment and
‘imagined touch’
. With this, we contribute to generating theory on physicalization. Our design vocabulary can support (1) creators through informing their design processes and highlighting design strategies, (2) educators, and (3) academics and practitioners to analyse existing physicalizations, and reflect on the impact of design decisions on interpretation and experience.