Tag Cloud

On displaying Tag, there are some important issue should be noticed.

1. Relationship with other words
Ⅰ semantic relationship
ex. "Information Visualization" and "Graphics"
Ⅱ hierarchy structure
ex. "Computer Science" and "Information Visualization"

2. Importance to the user

For now on, I would like to treat these tags as an social network.
The nodes are tags themselves, and the edges are the relationship between tags.

To display the similar concept of words, My Coloring Algorithm would be used.
However, Making nodes to display in similar color cannot shows the hierarchical structure of words. It seems that combine Treemap and Node-Link network is a good choice.
(For example, wordle is an good example, although the vertical layout is difficult for reading)

View tag's importance in Node size is trivial, However, Node size is depand on font size and the string length. the former can be solved by assign different size to each words, the later is still unsolved.