make close calls =?

I'm not familiar with the manner in which 'make close calls' has been used here, Ori.

Having said that, I would say it means that they make specific judgments about data that is too open ended.

Thank you JTT.

Should "data that is too open ended" be "data that are too open ended?'

This has been the pedantic, [in the worst possible sense of the word] viewpoint ie. that 'data' is a plural because it is a plural in Latin; so it should be the same for English. As I've pointed out that is complete nonsense because it's only followed for a few select words from a couple of select languages.

If this was an actual rule governing borrowed words, it would apply to all the borrowed words that have come into English from all languages. It most certainly does not!

You'll see 'data' as a plural most often in scientific/academic papers and in other print sources because it is often mandated by style manuals and the like with no thought given to how English actually works.


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M-W:

Usage Discussion of DATA

Data leads a life of its own quite independent of datum, of which it was originally the plural. It occurs in two constructions: as a plural noun (like earnings), taking a plural verb and plural modifiers (as these, many, a few) but not cardinal numbers, and serving as a referent for plural pronouns (as they, them); and as an abstract mass noun (like information), taking a singular verb and singular modifiers (as this, much, little), and being referred to by a singular pronoun (it). Both constructions are standard. The plural construction is more common in print, evidently because the house style of several publishers mandates it.

http://www.merriam-webster.com/dictionary/data
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AHD says, "The plural usage is still common, ... But more often scientists and researchers think of data as a singular mass entity like information, and most people now follow this in general usage.

http://education.yahoo.com/reference/dictionary/entry/data

Good point, JTT.