Ask the Director: How do I cite statistics?

Dear Director:

Can you tell me, how important is it to document statistics presented in articles? Is it enough that the editor has those references, urls, quotes sources in her files?

-- Per Cent
Dear Per:

The answer will vary depending on the publication and the article. If people turn to your publication for academic-quality research, then it probably makes sense to provide academic-style citations. And if the article is presenting research that your readers are likely to find unbelievable, it might be helpful to cite the source.

But in general, I think you should refer to the source but not necessarily give a full bibliographic reference. So you might say, "According to a 2012 study by the Pew Research Center," without going into more detail than that. Citing the source and year helps readers evaluate the quality of the statistic, and lends credibility to the story. If you go with this kind of highly abbreviated citation in the article, you might follow it with references in small print, or with a note saying that full citations are available in the online version in your website.

When you post the story online, of course, it's ideal to have a link to the original source that opens up in a new window.Most of your readers won't bother clicking that link, but knowing that they can do so builds confidence in your writing.

If the statistic you are citing is an opinion poll, there are some extra bits of information you'll want to include to help the reader judge the quality of the poll: number of people polled, margin of error and confidence level. You could do this parenthetically (based on a survey of 1,070 adults, margine of error plus or minus 3 percent at the 95 percent confidence level) or in a paragraph at the end of the story.

--Former Director, Doug Trouten