My presentation of a visualization for the Computer Supported Cooperative Work course at École Polytechnique Fédérale de Lausanne, December 2011.

1. Visualizing screen
overlaps
Adrian Tudor Pănescu
adrian.panescu@epfl.ch

2. The problem
●
”It's quite easy to overlap others' writing”;
●
”it's hard to know if you overlap existing
drawings”;
●
”Might be hard to avoid overlapping in some
cases”;
●
”It is a bit uncomfortable because it overlaps”;
●
”Sometimes it is hard to manage because we
should be careful to prevent our words from
overlapping”.
Visualizing screen overlaps 2

3. How to measure?
● Questionnaire:
● How much effort did it take to avoid overlapping?
● Did the participants contents overlapped?
● These are subjective!
● Can we use the system-interaction data?
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4. Idea
●
When writing/drawing each user ”claims”
some territory on the screen.
Source: http://jjguy.com/heatmap/
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9. Technical details
●
Library used for generating the heatmap:
http://jjguy.com/heatmap/;
●
Dot size (territory): 150 pixels;
●
The library was modified to fit our
scenario (multiple entities – the users);
●
A heatmap was generated for each user;
the resulted images were processed to
obtain the final result.
Visualizing screen overlaps 9