2018 House · AZ-1
Øptimus Analytics · fieldwork ended 2018-10-31 (6 days before the election) · 756 respondents · IVR
The poll said
Democrat 47.7% · Republican 45.35%
D+2.4
The certified result
Democrat 53.83% · Republican 46.14%
D+7.7
The arithmetic
- Poll margin = 47.7 − 45.35 = 2.35
- Actual margin = 53.832 − 46.144 = 7.688
- Signed miss = 2.35 − (7.688) = -5.338
- Absolute miss = |-5.338| = 5.338
The poll overstated the Republican by 5.3 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 56745, race ID 179 (538 database).