When talking about search engine results, the definition of quality can be subjective: when you get results you want, thats high quality; but when you dont, quality doesnt exist. But we all know that there are more ways than one to get results from search engines, you just need to know where to look.
The deep web, or the hidden web, are known as aggregations of data and information that is not easily searched by using the surface web, or the web found on major search engines like Yahoo, Google and others. The deep Web has been found to contain higher quality information, however, than you can find using surface web tools. One of the ways research groups and search engine specialists look at results from the deep web to determine whether quality results come from a search is by basing the results on a type of language review. For example they are looking for words of a higher reading level as well as results that may be more technical, as well as relevant to the subject matter.
In doing these tests, it is clear that the results of data searches in the deep web are of higher quality than the results from the surface web search engines. The information that is contained in deep web documents and generally has more relevant information, and does not have the same degree of fluff. Surface web sites are more often used for purposes other than information: advertising, selling things, marketing, attracting traffic or advertisers, and so on.
This measurement of quality of deep web vs. surface webalso holds true across all sectors of research. Fields such as finance, science, law, medicine and agriculture all have more authoritative and higher quality information within the hidden web, more than the surface web.
Another interesting finding is that deep Web sites provide as much as 10% more results than the surface web searches, and three times as many high quality documents! Consider this if you are doing a market research project or academic research you certainly dont want to rely on just Yahoo and Google!
You can find literally hundreds of deep Web search engine sites for every subject area. Even if over all the quality was not great, youd still have more than you would by using surface search methods. The duplication you also find these days over the surface web is not as much of a problem on the deep web. Deep Web sites have more unique data without question. If youre looking for the proverbial needle in a haystack, its imperative that you include deep Web search tools.