Where did my Lines go? Visualizing Missing Data in Parallel Coordinates

Alex Bäuerle Ulm University Christian van Onzenoodt Ulm University Simon der Kinderen Ulm University Jimmy Johansson Westberg Linköping University Daniel Jönsson Linköping University Timo Ropinski Ulm University

Computer Graphics Forum (Proc. of EuroVis 2022), 2022


We evaluate visualization concepts to represent missing values in parallel coordinates. We focus on the trade-off between the ability to perceive missing values and the concept’s impact on common tasks. For this purpose, we identified three missing value representation concepts: removing line segments where values are missing, adding a separate, horizontal axis onto which missing values are projected, and using imputed values as a replacement for missing values. For the missing values axis and imputed values concepts, we additionally add downplay and highlight variations. We performed a crowd-sourced, quantitative user study with 732 participants comparing the concepts and their variations using five real-world datasets. Based on our findings, we provide suggestions regarding which visual encoding to employ depending on the task at focus.



	title={Where did my Lines go? Visualizing Missing Data in Parallel Coordinates},
	author={B{\"a}uerle, Alex and van Onzenoodt, Christian and der Kinderen, Simon and Johansson Westberg, Jimmy and J{\"o}nsson, Daniel and Ropinski, Timo},
	journal={Computer Graphics Forum (Proc. of EuroVis (2022))},
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