This data are treated anonymously

I saw this sentence on a web service. But I think this sentence is wrong.

"This data are treated anonymously."

I think it should be either of these.

"This data is treated anonymously." "These data are treated anonymously."

Am I right?

Solution 1:

You are indeed correct. Formally, "data" is a collective noun, being the plural form of the Latin "datum". Thus, a grammarian would prefer "These data are...".

In popular usage, the word's Latin origins are being forgotten, and it is far more common these days for English speakers to treat "data" as a singular noun. For most users, "This data is..." would be the preferred form.

My guess is that the sentence you found started out as "This data is...", but was "corrected" with a plural noun when someone insisted the noun was plural. The writer likely failed to notice that the article should also have been changed to match.