Saving throw: Securing democracy with stats, spreadsheets, and 10-sided dice

Philip Stark with his boxes of ballots. (credit: Cyrus Farivar)

Today is Election Day in the United States, so we are resurfacing this story on auditing election results that originally ran in 2012.

NAPA, CALIFORNIA—Armed with a set of 10-sided dice (we’ll get to those in a moment), an online Web tool, and a stack of hundreds of ballots, University of California-Berkeley statistics professor Philip Stark spent last Friday unleashing both science and technology upon a recent California election. He wanted to answer a very simple question—had the vote counting produced the proper result?—and he had developed a stats-based system to find out.

On June 2, 6,573 citizens went to the polls in Napa County and cast primary ballots for supervisor of the 2nd District in one of California’s most famous wine-producing regions, on the northern edge of the San Francisco Bay Area. The three candidates—Juliana Inman, Mark van Gorder, and Mark Luce—would all have liked to come in first, but they really didn't want to be third. That's because only the two top vote-getters in the primary would proceed to the runoff election in November; number three was out.