|•||Buttons with higher probabilities w(i,j) tend to move to the center of the configuration.|
|•||Button size increases significantly from the center of the configuration to peripheral positions.|
|•||The algorithm tries to position buttons in order to minimize the distances between probably subsequent buttons as indicated by w(i,j) during a series of cursor movements.|
It is quite difficult to derive practical implications, since the work is rather theoretical. At the moment we do not consider any space between the buttons. They are placed together as tight as possible. Adopting the optimization algorithm to consider free spaces between the buttons will give a more precise answer to special GUI design tasks, e.g. the design of control panels, where detailed characteristics for usage are known.
Finally we want to thank our students Jutta Klein, Robert Henßen, and Roland Heinemann for their implementation of the optimization algorithm.
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