2010 House · MI-9
EPIC-MRA · fieldwork ended 2010-10-16 (17 days before the election) · 400 respondents · Live Phone
The poll said
Democrat 48% · Republican 43%
D+5.0
The certified result
Democrat 49.76% · Republican 47.23%
D+2.5
The arithmetic
- Poll margin = 48 − 43 = 5.00
- Actual margin = 49.764 − 47.229 = 2.535
- Signed miss = 5.00 − (2.535) = 2.465
- Absolute miss = |2.465| = 2.465
The poll overstated the Democrat by 2.5 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 51862, race ID 4667 (538 database).