2010 House · SD-1
Mason-Dixon Polling & Strategy · fieldwork ended 2010-10-20 (13 days before the election) · 800 respondents · Live Phone
The poll said
Democrat 43% · Republican 45%
R+2.0
The certified result
Democrat 45.89% · Republican 48.12%
R+2.2
The arithmetic
- Poll margin = 43 − 45 = -2.00
- Actual margin = 45.891 − 48.119 = -2.228
- Signed miss = -2.00 − (-2.228) = 0.227
- Absolute miss = |0.227| = 0.227
The poll overstated the Democrat by 0.2 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 52086, race ID 4818 (538 database).