The lengthening of papers' life expectancy: a diachronous analysis
The aging of scientific has generally been studied using synchronous approaches, i.e., based on references made by papers. This paper uses a diachronous model based on citations received by papers to study the changes in the life expectancy of three corpus of papers: papers from G6 and BRICS countries, papers published in Science, Nature, Physical Review and the Lancet and all papers divided into four broad fields: medical sciences, natural sciences and engineering, social sciences and arts and humanities. It shows that that: (i) life expectancy is extensively different from a corpus to another and may be either finite or infinite, meaning that the corpus would never be obsolete from a mathematical perspective; (ii) life expectancy for scientific literature has lengthened over the 1980-2000 period; (iii) life expectancy of developed countries' (G6) literature is on average shorter than that of emerging countries (BRICS).
life expectancy diachronous aging synchronous countries fields obsolescence life-time citation distribution journals