2008 President · MA
SurveyUSA · fieldwork ended 2008-10-27 (8 days before the election) · 658 respondents · IVR
The poll said
Democrat 56% · Republican 39%
D+17.0
The certified result
Democrat 61.36% · Republican 35.73%
D+25.6
The arithmetic
- Poll margin = 56 − 39 = 17.00
- Actual margin = 61.363 − 35.735 = 25.628
- Signed miss = 17.00 − (25.628) = -8.628
- Absolute miss = |-8.628| = 8.628
The poll overstated the Republican by 8.6 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 16606, race ID 723 (538 database).