2002 Senate · IL
SurveyUSA · fieldwork ended 2002-10-22 (14 days before the election) · 528 respondents · IVR
The poll said
Democrat 56% · Republican 36%
D+20.0
The certified result
Democrat 60.33% · Republican 38.02%
D+22.3
The arithmetic
- Poll margin = 56 − 36 = 20.00
- Actual margin = 60.334 − 38.020 = 22.314
- Signed miss = 20.00 − (22.314) = -2.314
- Absolute miss = |-2.314| = 2.314
The poll overstated the Republican by 2.3 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 54694, race ID 1655 (538 database).