Proceedings of the 8th International Conference on Intellectual ...

Harri Ketamo
Figure 3: Semantics with piece <strong>of</strong> content that include tags ‘interface design’ and ‘usability’
The next piece <strong>of</strong> content do have tags ‘usability’ and ‘graphical user interface’. The semantics grows
(figure 4) and ‘usability – interface’ –relation becomes even stronger. In this example, this relation
describes <strong>the</strong> context <strong>of</strong> <strong>the</strong>se videos with most explanative value. However, context based on only
few pieces <strong>of</strong> content is not relevant at all. According to our experiments, a useful semantics should
be based on more than 200 pieces <strong>of</strong> content; what more content that better semantics.
Figure 4: Semantics with piece <strong>of</strong> content that include tags ‘graphical user interface’ and ‘usability’
In real case, semantics won’t grow only based on relevant tags. There are always tags that are too
frequent and in that sense <strong>the</strong>ir explanative power is poor. For example tags like ‘news’ or ‘web’ are
included in that many tag sets that <strong>the</strong>y will build <strong>the</strong> most strongest relations between almost all
concepts. In figure 5 <strong>the</strong> phenomena is illustrated: ‘web’ and ‘news’ forms strong relations with all <strong>the</strong>
concepts (only some relations are drawn in order to remain <strong>the</strong> readability <strong>of</strong> <strong>the</strong> figure) and this
constructs <strong>the</strong> illusion <strong>of</strong> ‘web’ and ‘news’ as most important tags in this context.
We know that ‘web’ and ‘news’ are irrelevant and <strong>the</strong>y can also easily been extracted out <strong>of</strong> <strong>the</strong>
semantics. If a tag has 1) too many connections to o<strong>the</strong>r tags compared to average tag , 2) <strong>the</strong>
average strength <strong>of</strong> <strong>the</strong>se relations is high compared to o<strong>the</strong>r average strengths and most <strong>of</strong> all 3) <strong>the</strong>
variance in such strengths is relatively small, we can be sure that such tag is irrelevant in terms <strong>of</strong>
semantic search. Ano<strong>the</strong>r irrelevant group <strong>of</strong> tags consist <strong>of</strong> words that have only few relations with
small strength. Both kind <strong>of</strong> tags and relations can be excluded from <strong>the</strong> final semantics and <strong>the</strong>
semantic search is based only on tags that have well enough explanative power.
The use case, in brief, is following: At first user describes <strong>the</strong> subject in focus by typing several key
concepts (tags maybe) into UI’s definition field, for example ‘eyetracking and heatmaps’. Secondly,
<strong>the</strong> first types <strong>of</strong> agents start to search all possible content related to keywords. Currently search is
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