November 2009 Archive
Boulder County is once again doing a pretty comprehensive and savvy election audit, and you are invited to nominate some batches to be targeted for hand-counting! They have a press release on it.
The general auditing goal is "software independence", so we don't have to trust the black-box voting system we have. We do that by looking for the best independent evidence we can find for whether the preliminary outcomes of the election are correct. Specifically, we take a detailed report on the election results by batch, and carefully (but mostly randomly) select batches for hand-counting, to compare with the preliminary results.
The theory behind this is laid out at Principles and Best Practices for Post-Election Audits.
Boulder produced unusually fine-grained data for this audit, which helps greatly with the efficiency of the audit and confidence levels achieved. In fact, at a meeting at the American Statistical Association two weeks ago, we published a statement on the importance of small-batch reporting. Rather than reporting by big precincts, Boulder reported in batches averaging 150 ballots each. Vote counts for all 41 contests in each of batch are available.
Boulder also continues to pioneer a "budget-based" audit approach, which tries to maximize the confidence we can get out of auditing a given number of ballots. The initial budget for this audit is 21,000 ballot-contests (e.g. one contest on each of 21,000 ballots). So I'm guessing they'll be auditing about 140 units, which is an impressive number. But since the batches are small, the counting should be more accurate than with full-precinct audits, and the overall effort is reduced, without sacrificing statistical efficacy.
They're seeking nominations (e.g. of "unusual" results) for a given contest in a given audit unit and would love you to apply your own analysis or intuition. E.g. say "I nominate the 'City of Louisville Ballot Question 2A' contest in audit unit p005_mb_568 because the winner seems to have a surprisingly large share in that one" (which probably isn't true, but you get the idea). More details would be welcome. One technique used last year by auditing guru Mark Lindeman was constructing a model to predict votes in one contest based on how voters in the same batch voted in other contests, and identifying vote counts that seemed out of character.
November 11 is the deadline to submit nominations. They will probably choose some at random, and I'm hoping they'll also choose some on merit.
Check out the audit page and all the data at
Helpful "Usage Notes" are in the third zip file there (the only one you really need, which contains the processed data to be audited and the spreadsheet that will actually implement the audit), i.e.
It also includes their detailed plan. The plan doesn't quite match the current state-of-the-art for dealing with discrepancies (represented by Philip Stark's work in California), and having an effective canvass of the chain of custody and reconciliation of the number of ballots in each ballot style is also necessary. Verifying chain-of-custody for mail ballot elections is a very very hard task of course. But this audit is way ahead of most of the country. Hillary Hall, Don Hayden, and the rest of the team should be commended on their work.
See other election info here: http://www.bouldercounty.org/clerk/elections/
This is all based on the audit we did last year in Boulder: http://bcn.boulder.co.us/~neal/elections/boulder-audit-08-11/
Your comments and analysis would be most welcome!