Open access and sources of full-text articles in Google Scholar in different subject fields

Abstract

Google Scholar, a widely used academic search engine, plays a major role in finding free full-text versions of articles. But little is known about the sources of full-text files in Google Scholar. The aim of the study was to find out about the sources of full-text items and to look at subject differences in terms of number of versions, times cited, rate of open access availability and sources of full-text files. Three queries were created for each of 277 minor subject categories of Scopus. The queries were searched in Google Scholar and the first ten hits for each query were analyzed. Citations and patents were excluded from the results and the time frame was limited to 2004-2014. Results showed that 61.1 % of articles were accessible in full-text in Google Scholar; 80.8 % of full-text articles were publisher versions and 69.2 % of full-text articles were PDF. There was a significant difference between the means of times cited of full text items and non-full-text items. The highest rate of full text availability for articles belonged to life science (66.9 %). Publishers' websites were the main source of bibliographic information for non-full-text articles. For full-text articles, educational (edu, ac.xx etc.) and org domains were top two sources of full text files. ResearchGate was the top single website providing full-text files (10.5 % of full-text articles).

Scholarly publications beyond pay-walls: increased citation advantage for open publishing

“…These results are in accordance with our earlier findings (Mikki et al, accepted by Library Hi Tech) regarding climate impact on ancient societies (74%), and findings by Jamali and Nabavi (2015) who reported an OAvshare between 60% and 70%, dependent on sub-field. According to these studies, climate-related publications seem to be ahead when it comes to open publishing.…”

“…These findings are in accordance with findings by the previously-mentioned studies (Archambault et al, 2016;Jamali & Nabavi, 2015;Pitol & De Groote, 2014) and confirm in fact an increased citation advantage of open documents. We conclude that open publishing is a good strategy for maximizing research impact.…”

“…Archambault et al (2013) Jamali and Nabavi (2015) and Pitol and De Groote (2014) reported the highest shares so far, 74%, 61% and 70% respectively. These findings are limited to specific cases and sets of publications and call for further investigations and verification.…”

Un panorama académico de dos caras: retrato de los documentos altamente citados en Google Scholar (1950-2013)

“…In any case, these values are consistent with those published by Archambault et al (2013), who found that over 40% of the articles from their sample were freely accessible; higher than those by Khabsa and Giles (2014) and Björk et al (2010), who found only a 24% and 20.4% of open access documents respectively; and much lower than Jamali and Nabavi (2015) and Pitol and De Groote (2014), who found 61.1% and 70% respectively.…”

“…1 There is a low Pearson's correlation between the number of citations and the number of versions (r= 0.2; n= 64,000). This value is similar to that obtained by Jamali and Nabavi (2015), who found a weak positive correlation between the number of versions and the citation counts for full-text articles (r = 0.346; n = 4426). Pitol and De Groote (2014) found low values as well (r= 0.257; n= 982) when describing the GS versions for articles stored in institutional repositories from three US universities.…”