Expert: Dan Smith - 11/25/2003

Question
Hello Dan-

My question is if the the word "data" should be treated as a plural at all times? I'm uncertain about writing statements like "the data described is formatted (...)" or "the data described are formatted (...)".

Also, if you can think of any rule of thumb to know when "data" or "datum" should be used, I would also appreciate it. The distinction between one and the other might be obvious, but still I thought of asking.

Thank you!
Fernando

Answer
You can't win on this one. Here is what the Dictionary of Modern American Usage (Garner, 2000)has to say on the subject:

"Data is a skunked term: whether you write 'data are' or 'data is,' you're likely to make some readers raise their eyebrows. Technically a plural, 'data' has, since the 1940s, been increasingly thought of as a mass noun taking a singular verb. But in more or less formal contexts it is preferably treated as a plural--e.g.: 'While recent U.S. Census data show that the average working woman's pay has declined in the '90s, hihgly educated, high-paid wome nkeep gaining ground.' ....

"Many writers use it as a singular, however, risking their credibility wiht some readers (concededly a shrinking minority)....

"The one context in which the singular use of 'data' might be allowed is in computing and allied disciplines. ....

(this discussion goes on at some length.)

"As a historian of the English language once put it, 'A student with one year of Latin [knows] that data and phenomena are plural.' .... And that's what makes the term skunked: few people use it as a plural, yet many know that technically it is a plural. Whatever you do, if you use data in a context in which its number becomes known, you'll bother some of your readers. Perhaps 50 years from now--maybe sooner, may later--the term will no longer be skunked: everybody will accept it as a collective. But not yet."

I'm like everyone else, I mix and match on this one in conversation, but in writing I use the formally correct construction. That is what I recommend.

By the way, I strongly recommend the Garner book (about $30.00). It is not only useful, with exceptionally helpful explanations, it is entertaining as well.

Hope this helps.