2010 Senate · IL
Scott Rasmussen (Rasmussen Reports) · fieldwork ended 2010-10-30 (3 days before the election) · 1,000 respondents · IVR
The poll said
Democrat 42% · Republican 46%
R+4.0
The certified result
Democrat 46.42% · Republican 48.02%
R+1.6
The arithmetic
- Poll margin = 42 − 46 = -4.00
- Actual margin = 46.416 − 48.015 = -1.599
- Signed miss = -4.00 − (-1.599) = -2.401
- Absolute miss = |-2.401| = 2.401
The poll overstated the Republican by 2.4 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 32806, race ID 1518 (538 database).