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Incidentally, the Stanford study would not have been possible even five years ago—the professor who conducted it would have had trouble obtaining accurate data. But in 2001, a Dutch company called VNU introduced Nielsen BookScan, which reports industry-wide sales figures and is available only by subscription. Like the national best-seller lists, BookScan relies on sampling—in their case, about 4,500 retailers—but BookScan reveals hard data on unit sales for books. The Washington Post bases its rankings on BookScan data, but Nielsen requires that the Post keep unit sales figures out of the paper.
Of course, the absence of definitive sales data on best-seller lists generally suits publishers just fine since the uncomfortable truth is that sales of most books, even those doing relatively well, are pretty low. Publishers like to promote books as "national best sellers" in part because the term creates a sense of momentum and critical consensus that the phrase "over 25,000 copies sold"—which would actually be a pretty good figure for literary fiction sales in hardcover—does not.
Clearly, publishers can't call any old book a "national best seller," but there are no industry-wide rules about how well books must perform to earn the "national" part of the claim. A ranking on any of the lists with a country-wide survey (such as Amazon or USA Today) clearly suffices, but publishers have varying policies on how many regional lists a book must appear on (and how widely dispersed those lists must be) before the title can be promoted as a "national" hit. What makes these distinctions important is that there's more than just a gold "best seller" sticker at stake: Many bookstores discount whatever is on the best-seller list—often the Times' list—and display the books prominently, which can further accelerate sales. At this point, a book's reputation can snowball: Anxious buyers get the sense that they should read a book because other people are doing it. The Stanford study offers the first quantification of the sales benefit from making the Times hardcover fiction list: While it has no discernible impact for famous authors like Danielle Steel or John Grisham, on average it gives a 57 percent boost to first-time authors who make the list.
Correction, Oct. 14, 2004: A version of this piece originally published on June 17, 2004, contained the following errors:
The column inaccurately suggested that publishers deliberately "suppress" information about book sales, withholding "hard data" from the editors who draw up best-seller lists. The column should have noted that the editors of best-seller lists, concerned that publishers might inflate their sales figures, have long preferred to gather data from independent sources that do not have a stake in the success of a given title.
The column inaccurately reported that "most" authors "cannot get access to hard data" about sales of their own books and "have to trust they're not being cheated out of royalties." In fact, though authors may have trouble getting timely access to such data, publishers have a contractual obligation to send authors a statement detailing book sales and royalties within six to nine months of a book's release.
The column stated, imprecisely, that visitors to the Web site IMDb.com could "find out exactly how much a film took in at the box office." The statement was not intended as an assessment of the accuracy of those figures.
The original column included a paragraph on authors who try "to game the system"—to manipulate the best-seller list by buying their own books in bulk—and incompletely recounted the case of David Vise, a writer who was suspected of trying to do so in 2002. The original column stated that Vise purchased 20,000 copies of his book The Bureau and the Mole and "was only caught when he tried to return 17,500 of them." Both figures were among those reported at the time, but documents Vise provided to the Washington Post showed that he purchased 18,468 books and returned 9,678 of them, and the number of books he bought and sold was never definitively established. The column also noted that Vise's actions were "widely seen" as an effort to win a plum spot on the best-seller list without detailing who saw them that way, and its acknowledgment that Vise denied the charges was inappropriately dismissive.