2018 Senate · MI
Gravis Marketing · fieldwork ended 2018-10-29 (8 days before the election) · 764 respondents · IVR/Online Panel
The poll said
Democrat 54% · Republican 41%
D+13.0
The certified result
Democrat 52.26% · Republican 45.76%
D+6.5
The arithmetic
- Poll margin = 54 − 41 = 13.00
- Actual margin = 52.262 − 45.756 = 6.506
- Signed miss = 13.00 − (6.506) = 6.494
- Absolute miss = |6.494| = 6.494
The poll overstated the Democrat by 6.5 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 56620, race ID 106 (538 database).