Group items tagged

How is the size of the World Wide Web estimated?
The estimated minimal size of the indexed World Wide Web is based on the estimations of the numbers of pages indexed by Google, Bing, Yahoo Search and Ask. From the sum of these estimations, an estimated overlap between these search engines is subtracted. The overlap is an overestimation; hence, the total estimated size of the indexed World Wide Web is an underestimation.Since the overlap is subtracted in sequence, starting from one of the four search engines, several orderings (and total estimations) are possible. We present two total estimates, one starting with Yahoo (YGBA) and one starting with Google (GYBA). The figure reported at the top of the page refers to the YGBA estimation.

Zipf's law ( /ˈzɪf/), an empirical law formulated using mathematical statistics, refers to the fact that many types of data studied in the physical and social sciences can be approximated with a Zipfian distribution, one of a family of related discrete power law probability distributions. The law is named after the linguist George Kingsley Zipf who first proposed it (Zipf 1935, 1949), though J.B. Estoup appears to have noticed the regularity before Zipf.[1]