more accurate, interpretations than automated classification systems are capable of

making, but suffers from its own sources of error.  The filtering software companies

involved here have limited staff, of between eight and a few dozen people, available for

hand reviewing Web pages.  The reviewers that are employed by these companies base

their categorization decisions on both the text and the visual depictions that appear on the

sites or pages they are assigned to review.  Human reviewers generally focus on English

language Web sites, and are generally not required to be multi lingual.  

Given the speed at which human reviewers must work to keep up with even a

fraction of the approximately 1.5 million pages added to the publicly indexable Web each

day, human error is inevitable.  Errors are likely to result from boredom or lack of

attentiveness, overzealousness, or a desire to  err on the side of caution  by screening out

material that might be offensive to some customers, even if it does not fit within any of

the company's category definitions.  None of the filtering companies trains its reviewers

in the legal definitions concerning what is obscene, child pornography, or harmful to

minors, and none instructs reviewers to take community standards into account when

making categorization decisions. 

Perhaps because of limitations on the number of human reviewers and because of

the large number of new pages that are added to the Web every day, filtering companies

also widely engage in the practice of categorizing entire Web sites at the  root URL, 

rather than engaging in a more fine grained analysis of the individual pages within a Web

site.  For example, the filtering software companies deposed in this case all categorize the

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