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methods on data sets with distinct characteristics in
terms of sparseness and distance distribution. When
there was the need to isolate one of the cluster charac-
teristics, we used synthetic 2D scatter plot examples.
Our findings were that density and shape of clus-
ters significantly affect the perception during a visual
inspection leading to biased instead of balanced re-
sults in our experiments. Cluster size did not lead to
significant affects. The orientation of the scatter plots
did also not affect the interpretation significantly. In
general, though, we have observed that cluster prop-
erties do influence the outcome. Hence, perception is
an important aspect when analyzing projections that is
not captured in the typically applied numerical quality
estimates.
ACKNOWLEDGEMENTS
This work was supported by the research center on
Visual Communication and Expertise (VisComX) at
Jacobs University, Bremen, Germany.
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