How old is the Web? Characterizing the age and the currency of the European scientific Web

Abstract

The aim of this paper is to model and study the age of the Web using a sample of about four million of web pages from the 16 European Research Area countries obtained during 2004 and 2005. Web page time-stamp (date when the web pages were created or last changed for last time), format and size in bytes data have been analysed. Several indicators are introduced to measure longitudinal aspects of the Web. Half-age is proposed as a measure of the age distribution because this is found to be exponential. "Web Update Index" and "Lifespan Index" are introduced to measure the changing rate of a small sample over time. Results show that the British Web space has the youngest Web pages while the Greek and Belgian ones have the oldest. The study also compared Web pages topics and found that Biology pages are more stable than Physics pages.

Differences between web sessions according to the origin of their visits

“…Thus, we observed 3586 (25,3%) 2-sessions, 3188 (22,5%) 3-sessions, 2227 (15,7%) 4-sessions and so on. We also appreciated that the length distribution of sessions follows an exponential decay (Bianco et al, 2005) similar to the observed in other longitudinal web phenomena (Ortega, Cothey, & Aguillo, 2009). The fit of the distribution is high (R 2 = .98), so we may estimate the number of sessions by length not identified.…”