2018 House · CA-50
SurveyUSA · fieldwork ended 2018-10-27 (10 days before the election) · 547 respondents · IVR/Online Panel
The poll said
Democrat 45% · Republican 48%
R+3.0
The certified result
Democrat 48.28% · Republican 51.72%
R+3.4
The arithmetic
- Poll margin = 45 − 48 = -3.00
- Actual margin = 48.285 − 51.715 = -3.430
- Signed miss = -3.00 − (-3.430) = 0.431
- Absolute miss = |0.431| = 0.431
The poll overstated the Democrat by 0.4 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 56547, race ID 237 (538 database).