2008 House · OR-5
SurveyUSA · fieldwork ended 2008-10-27 (8 days before the election) · 668 respondents · IVR
The poll said
Democrat 55% · Republican 31%
D+24.0
The certified result
Democrat 54.26% · Republican 38.34%
D+15.9
The arithmetic
- Poll margin = 55 − 31 = 24.00
- Actual margin = 54.255 − 38.335 = 15.920
- Signed miss = 24.00 − (15.920) = 8.080
- Absolute miss = |8.080| = 8.080
The poll overstated the Democrat by 8.1 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 64361, race ID 4355 (538 database).