The Sampling Lens:
making sense of saturated visualisation

Geoff Ellis
Lancaster University, UK.
< Geoff on the web >


Enrico Bertini
Univ. Roma 1, "La Sapienza", Italy
< Enrico on the web >


Alan Dix
Lancaster University, UK
< Alan on the web >

Interactive Poster at CHI'2005, 2-7 April 2005, Portland, USA.


Information visualisation systems frequently have to deal with large amounts of data, which often leads to saturated areas in the display with considerable overplotting. This paper introduces the Sampling Lens, a novel tool that utilises random sampling to reduce the clutter within a moveable region, thus allowing the user to uncover any potentially interesting patterns and trends in the data. We demonstrate the versatility of the tool by adding sampling lenses to scatter and parallel co-ordinate visualisations. We also consider some implementation issues and present initial user evaluation results.

Keywords: sampling, random sampling, lens, clutter, density reduction, overplotting, information visualisation

Full reference:
G. Ellis, E. Bertini and A. Dix (2005). The Sampling Lens: making sense of saturated visualisation Proceedings of CHI'2005 , ACM Press. pp. 1351-1354.
Download poster (PDF, 15Mb)
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Poster: download in PDF (15Mb)


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Figure 1. Parcel data scatter plot example

Figure 2. Revealing hidden pattern

Figure 3. Parallel coordinate example

Figure 4. Implementation architectures for sampling lens

Alan Dix 8/4/2005