It’s time to disrupt your faith in the accuracy of free academic literature searching, I’m sorry to say.
Scirus is a well-established and popular search engine. It’s the main one that I recommend to people who want to search the world of academic research for free.
However, we have discovered a couple of significant problems. The first one is a bit hard to demonstrate (you’ll need to try it for yourself), but is to do with the way Scirus interprets boolean terms which results in what looks like an identical search string bringing back a very different number of hits when simply re-run. The command structure is being re-interpreted and changed somewhere along the line, although when you check to see if your search string has changed, it is displayed as identical. So, what has happened and which set of results is the correct one?
Secondly, there is a large number of articles which don’t fit into any of the Information Types or Subject Areas at all and thus will be excluded from your search results. We alerted Scirus to this significant anomaly using an example. I am pleased to say that Scirus took this on board promptly and having tried this for themselves and realised the situation, this is how Scirus explains (and acknowledges) the problem:
The problem lies in the fact that not all records on Scirus are classified with respect to information type and subject area. This means that any record not being classified – as is the case with the record you are referring to – is impossible to find if you do not set the search to “All information types” and “All subject areas”. Unfortunately we do not have an Information type “Other” or subject area “not classified”.
I hope that Scirus will work to resolve this problem in the not too distant future. In the meantime, in order to ensure that you don’t exclude all these other hits from your results, you’ll need to run your search across all subject areas and all information types. Then use the menus on the left-hand side of the results list to view different information types or subjects.
Well, I suppose there’s no such thing as a free lunch – unless you don’t mind a sizeable portion of it to be missing!
And of course, I’d be interested in hearing about your experiences with science search engines – positive or negative. Now I really should go and work out how to explain the first boolean-related problem to Scirus as I haven’t done so yet – it’s a bit more tricky to demonstrate (and possibly to rectify too).