Nate Silver: Pollster Ratings v4.0: Results

[tritsofme]

For a complete methodological discussion, see http://www.fivethirtyeight.com/2010/06/pollster-ratings-v40-methodology.html">here. I'm just going to reiterate just a few very high-level bullet points.
-- These ratings pertain to just one particular type of poll: those which attempt to forecast election outcomes, and do so in the public domain.

-- These ratings reflect polling for President (general and primary elections), U.S. Senate, U.S. House, and gubernatorial races since 1998. More recent cycles are weighted more heavily. This is a truly massive amount of data: roughly 4,700 polls.

-- The variable called rawscore is the most direct measure of a pollster's track record. However, it is much inferior to PIE -- or Pollster-Introduced Error -- for evaluating the effectiveness of different pollsters on a going-forward basis. Because polling involves a great deal of luck in the near-term, rawscores must be substantially regressed toward the mean. However, different types of pollsters are regressed to different means. In particular, pollsters that have made a commitment to transparency and disclosure have been shown to have superior results over the long-run. The way we measure this is whether the pollster was a member of either the NCPP or the AAPOR Transparency Initiative as of 6/1/10.

-- PIE is expressed as a positive number and reflects the amount of error that a pollster introduces above and beyond that which is unavoidable due to things like sampling variance. The lower a firm's PIE the better.

The list below provides ratings for all firms with a minimum of 10 polls. A complete list of ratings (including for firms with fewer than 10 polls) follows it below the fold.



http://www.fivethirtyeight.com/2010/06/pollster-ratings-v40-results.html

I find these things pretty interesting. Not surprised to Zogby Interactive at the bottom of the list.

[Scuba]

1. Hey everybody. My rigged poll shows Americans love Republicans. Jump on board.

Love, Rupert.