Attribute Usage

We examined the distribution of attributes. The average number of total attributes per document was 29. The average number of unique attributes per document was 4.

We examined the most popular attributes. The graph shows the top ten attributes (ranked according to the number of documents in which the attribute appeared at least once). HREF appeared an average of 14 times per document.

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Ten Most-Used Attributes

We also examined the least popular attributes. Several attributes, ACCEPT-CHARSET, AXIS, CHAROFF, and CONTROLS, were used zero times in our data set of 2.6 million HTML documents. A number of other attributes appeared a very limited number of times.