2010 Senate · ID
Mason-Dixon Polling & Strategy · fieldwork ended 2010-10-21 (12 days before the election) · 625 respondents · Live Phone
The poll said
Democrat 20% · Republican 64%
R+44.0
The certified result
Democrat 24.93% · Republican 71.17%
R+46.2
The arithmetic
- Poll margin = 20 − 64 = -44.00
- Actual margin = 24.928 − 71.175 = -46.247
- Signed miss = -44.00 − (-46.247) = 2.247
- Absolute miss = |2.247| = 2.247
The poll overstated the Democrat by 2.2 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 32661, race ID 1517 (538 database).