Dear Professor Mean,
Should I write “data is” or “data are”?*
I’ve always been open minded and allow people to say either. But the purists among us will insist that data is the plural of datum. These are the people who took Latin in High School while you and I were taking Wood Shop.
If you’re writing something that someone else will review, always use “data are”. It will make the purists happy and you won’t hear any criticism from the rest of us (the impurists?).
I have changed the format of these web pages to use “data are” because I want the proof readers of these web pages to look for other things.
In support of “data are”
Tyler Krupa, APA Style blog Data Is, or Data Are? Excerpt: As noted in the sixth edition of the Publication Manual (p. 79), the plural form of some nouns of foreign origin—particularly those that end in the letter a—may appear to be singular and can cause authors to select a verb that does not agree in number with the noun. This is certainly the case with the word data. As shown in the Publication Manual (p. 96), the word datum is singular, and the word data is plural. Plural nouns take plural verbs, so data should be followed by a plural verb.
In support of “data is”
Guardian Observer Style Guide. Excerpt: takes a singular verb (like agenda), though strictly a plural; you come across datum, the singular of data, about as often as you hear about an agendum.
Glenn Vanderburg Data Is. O’Reilly Developer Weblogs. Excerpt: I know that “data” is technically the plural of “datum”. But I find it jarring when I read that “the data are transmitted” somewhere. In common usage (both speech and informal writing) that data “is transmitted..
Charles Carlson. Is “Data” Singular or Plural? Excerpt: “We’ve received several requests to address Latin plurals, so today we’re going to tackle a tricky one. A listener called with this request: Hi, Grammar Girl. This is Adam from Peoria. I was wondering if you could go over the usage of the word data, as in The data are correct or The data is correct. Thanks.”
Neha Srivastava Editor’s Manual blog, 2019-10-10. Excerpt: The word data is now generally treated as singular, much like the word information. Its use as a plural word is now restricted mainly to academic and scientific writing.
You can find an earlier version of this page on my original website.