2012 President · SD
Nielson Brothers Polling · fieldwork ended 2012-11-02 (4 days before the election) · 633 respondents · IVR
The poll said
Democrat 41% · Republican 53%
R+12.0
The certified result
Democrat 39.87% · Republican 57.89%
R+18.0
The arithmetic
- Poll margin = 41 − 53 = -12.00
- Actual margin = 39.866 − 57.889 = -18.023
- Signed miss = -12.00 − (-18.023) = 6.023
- Absolute miss = |6.023| = 6.023
The poll overstated the Democrat by 6.0 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 30790, race ID 694 (538 database).