How is JURN’s total number of ejournals calculated? Well, it’s a number that’s been built up incrementally since the beta. But a rough checking calculation at Jan 2011 would go something like this:—

* 2,580 non-duplicate English-language titles, as listed in the 2,700-link JURN Directory.
* Around 620 marginal ‘partly in English’ titles that I didn’t enter in the English-language JURN Directory, and yet which are not on Revues / Persee / Dialnet / Cairn since they’re not in Spanish/French.
* 2,792 Spanish titles in the arts and humanities and ‘philologies’, as currently indexed via Dialnet. 1,367 titles on Dialnet currently have full-text, and perhaps 600 of these offer articles relevant to the arts and humanities. *
* 105 older French titles on Persee.
* 274 titles on Revues, perhaps 260 if a handful of geography titles and ‘collections’ are discounted.
* Around 250 relevant titles via the Hungarian central index.
* Around 180 relevant French titles via Cairn.
* Around 250 humanities titles from the Central America region via Redalyc.
* Around 170 arts and humanities titles in Portuguese, via Livre.
* Perhaps another 200 (perhaps more) non-English titles from various national amalgamation services such as those in Serbia, Taiwan, Singapore, Mexico, Catalonia, etc.

That would give a grand total of about 5,200 titles indexed.

However, if only those titles that carry at least some English articles are to be counted, then the calculation is more like: 2,580 English titles + 620 known partly-English + another 700 unknown partly-English titles hidden among the total at Dialnet / Redalyc, et al = 3,900.

* Indexing Dialnet does bring in some article record pages that don’t contain links to full-text. JURN indexes Dialnet via three URLs that bring in: i) just the main index pages for journals (not the TOC pages), ii) full-text PDF articles hosted on Dialnet, and iii) article record pages. The latter may or may not contain links to full-text (I estimate about a one-in-six chance of full-text from a Dialnet record, in arts and humanities searches). However, for those searching for English search-terms, this is unlikely to flood the search results with masses of records that only contain citations / abstracts. I think it’s a price worth paying, when weighed against the wealth of full-text material that it can bring in for a searcher.