<p>One important consideration is that the OP should easily be able to find appropriate tags when posting their question.  The current interface is a text input box that performs a real-time prefix search of the tags.  When someone is concerned about a large dataset, what might they start typing to find appropriate tags?  Not "high-dimensional," I don't think!  The prefix ought to be "large" or "big"--something simple like that.  But that presumes the tag system uses prefixes as modifiers.</p>

<p>Alternatively, create a set of tags that modify the word "data" with <em>suffixes</em>.  In this scheme, an OP concerned specifically about data might type the word "data" to produce a short list of data-related tags, such as "database", "database-large", "database-high-dimensional", "data-format", etc., allowing them to choose appropriately from this list.</p>
