2012 President · OH
Suffolk University · fieldwork ended 2012-10-20 (17 days before the election) · 600 respondents · Live Phone
The poll said
Democrat 46.5% · Republican 46.6%
R+0.1
The certified result
Democrat 50.67% · Republican 47.69%
D+3.0
The arithmetic
- Poll margin = 46.5 − 46.6 = -0.10
- Actual margin = 50.667 − 47.688 = 2.979
- Signed miss = -0.10 − (2.979) = -3.078
- Absolute miss = |-3.078| = 3.078
The poll overstated the Republican by 3.1 points and had the wrong leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 30199, race ID 688 (538 database).